JEE Mains
2026
MCQ
Let $A, B$ and $C$ be three $2 \times 2$ matrices with real entries such that $B=(I+A)^{-1}$ and $\mathrm{A}+\mathrm{C}=\mathrm{I}$.
If $\mathrm{BC}=\left[\begin{array}{cc}1 & -5 \\ -1 & 2\end{array}\right]$ and $\mathrm{CB}\left[\begin{array}{l}x_1 \\ x_2\end{array}\right]=\left[\begin{array}{l}12 \\ -6\end{array}\right]$, then $x_1+x_2$ is
JEE Mains
2026
MCQ
Let $P=\left[p_{i j}\right]$ and $Q=\left[q_{i j}\right]$ be two square matrices of order 3 such that $q_{\mathrm{ij}}=2^{(\mathrm{i}+\mathrm{j}-1)} \mathrm{p}_{\mathrm{ij}}$ and $\operatorname{det}(\mathrm{Q})=2^{10}$. Then the value of $\operatorname{det}(\operatorname{adj}(\operatorname{adj} \mathrm{P}))$ is:
JEE Mains
2026
MCQ
Let $f(x)=\int \frac{7 x^{10}+9 x^8}{\left(1+x^2+2 x^9\right)^2} d x, x>0, \lim\limits_{x \rightarrow 0} f(x)=0$ and $f(1)=\frac{1}{4}$.
If $\mathrm{A}=\left[\begin{array}{ccc}0 & 0 & 1 \\ \frac{1}{4} & f^{\prime}(1) & 1 \\ \alpha^2 & 4 & 1\end{array}\right]$ and $\mathrm{B}=\operatorname{adj}(\operatorname{adj} \mathrm{A})$ be such that $|\mathrm{B}|=81$, then $\alpha^2$ is equal to
JEE Mains
2026
MCQ
The system of linear equations
$ \begin{aligned} & x+y+z=6 \\ & 2 x+5 y+a z=36 \\ & x+2 y+3 z=b \end{aligned} $
has :
JEE Mains
2026
MCQ
Among the statements :
I: If $\left|\begin{array}{ccc}1 & \cos \alpha & \cos \beta \\ \cos \alpha & 1 & \cos \gamma \\ \cos \beta & \cos \gamma & 1\end{array}\right|=\left|\begin{array}{ccc}0 & \cos \alpha & \cos \beta \\ \cos \alpha & 0 & \cos \gamma \\ \cos \beta & \cos \gamma & 0\end{array}\right|$, then $\cos ^2 \alpha+\cos ^2 \beta+\cos ^2 \gamma=\frac{3}{2}$, and
II: If $\left|\begin{array}{ccc}x^2+x & x+1 & x-2 \\ 2 x^2+3 x-1 & 3 x & 3 x-3 \\ x^2+2 x+3 & 2 x-1 & 2 x-1\end{array}\right|=\mathrm{p} x+\mathrm{q}$, then $\mathrm{p}^2=196 \mathrm{q}^2$,
JEE Mains
2026
MCQ
Let n be the number obtained on rolling a fair die. If the probability that the system
$ \begin{aligned} & x-\mathrm{n} y+z=6 \\ & x+(\mathrm{n}-2) y+(\mathrm{n}+1) z=8 \\ & \quad(\mathrm{n}-1) y+z=1 \end{aligned} $
has a unique solution is $\frac{k}{6}$, then the sum of $k$ and all possible values of $n$ is :
JEE Mains
2026
MCQ
If $X=\left[\begin{array}{l}x \\ y \\ z\end{array}\right]$ is a solution of the system of equations $A X=B$, where $\operatorname{adj} A=\left[\begin{array}{ccc}4 & 2 & 2 \\ -5 & 0 & 5 \\ 1 & -2 & 3\end{array}\right]$ and $\mathrm{B}=\left[\begin{array}{l}4 \\ 0 \\ 2\end{array}\right]$, then $|x+y+z|$ is equal to :
JEE Mains
2026
MCQ
If $\mathrm{A}=\left[\begin{array}{ll}2 & 3 \\ 3 & 5\end{array}\right]$, then the determinant of the matrix $\left(\mathrm{A}^{2025}-3 \mathrm{~A}^{2024}+\mathrm{A}^{2023}\right)$ is
JEE Mains
2026
MCQ
If the system of equations
$ 3x + y + 4z = 3 $
$ 2x + \alpha y - z = -3 $
$ x + 2y + z = 4 $
has no solution, then the value of $ \alpha $ is equal to:
JEE Mains
2026
MCQ
For the matrices $A = \begin{bmatrix} 3 & -4 \\ 1 & -1 \end{bmatrix}$ and $B = \begin{bmatrix} -29 & 49 \\ -13 & 18 \end{bmatrix}$, if $(A^{15} + B) \begin{bmatrix} x \\ y \end{bmatrix} = \begin{bmatrix} 0 \\ 0 \end{bmatrix}$, then among the following which one is true?
JEE Mains
2026
MCQ
If the system of linear equations :
$ \begin{aligned} & x+y+z=6 \\ & x+2 y+5 z=10 \\ & 2 x+3 y+\lambda z=\mu \end{aligned} $
has infinitely many solutions, then the value of $\lambda+\mu$ equals:
JEE Mains
2026
MCQ
Let $A=\left[\begin{array}{lll}\alpha & 1 & 2 \\ 2 & 3 & 0 \\ 0 & 4 & 5\end{array}\right]$ and $B=\left[\begin{array}{ccc}1 & 0 & 0 \\ 0 & -5 \alpha & 0 \\ 0 & 4 \alpha & -2 \alpha\end{array}\right]+\operatorname{adj}(A)$. If $\operatorname{det}(B)=66$, then $\operatorname{det}(\operatorname{adj}(A))$ equals :
JEE Mains
2026
MCQ
The sum of all possible values of $\theta \in[0,2 \pi]$, for which the system of equations :
$ \begin{aligned} & x \cos 3 \theta-8 y-12 z=0 \\ & x \cos 2 \theta+3 y+3 z=0 \\ & x+y+3 z=0 \end{aligned} $
has a non-trivial solution, is equal to :
JEE Mains
2026
MCQ
Let $\mathrm{A}=\left[\begin{array}{lll}1 & 0 & 0 \\ 3 & 1 & 0 \\ 9 & 3 & 1\end{array}\right]$ and $\mathrm{B}=\left[\mathrm{b}_{i j}\right], 1 \leq i, j \leq 3$. If $\mathrm{B}=\mathrm{A}^{99}-\mathrm{I}$, then the value of $\frac{\mathrm{b}_{31}-\mathrm{b}_{21}}{\mathrm{~b}_{32}}$ is :
JEE Mains
2026
MCQ
If $f: \mathbf{N} \rightarrow \mathbf{Z}$ is defined by
$ f(n)=\left|\begin{array}{ccc} n & -1 & -5 \\ -2 n^2 & 3(2 k+1) & 2 k+1 \\ -3 n^3 & 3 k(2 k+1) & 3 k(k+2)+1 \end{array}\right|, k \in N, $
and $\sum\limits_{n=1}^k f(n)=98$, then $k$ is equal to :
JEE Mains
2026
MCQ
Let M be a $3 \times 3$ matrix such that $\mathrm{M}\left(\begin{array}{l}1 \\ 0 \\ 0\end{array}\right)=\left(\begin{array}{l}1 \\ 2 \\ 3\end{array}\right), \mathrm{M}\left(\begin{array}{l}0 \\ 1 \\ 0\end{array}\right)=\left(\begin{array}{l}0 \\ 1 \\ 2\end{array}\right)$ and $\mathrm{M}\left(\begin{array}{l}0 \\ 0 \\ 1\end{array}\right)=\left(\begin{array}{c}-1 \\ 1 \\ 1\end{array}\right)$. If $\mathrm{M}\left(\begin{array}{l}x \\ y \\ z\end{array}\right)=\left(\begin{array}{c}1 \\ 7 \\ 11\end{array}\right)$, then $x+y+z$ equals :
JEE Mains
2026
MCQ
Let A be a $3 \times 3$ matrix such that
$ \mathrm{A}^{\mathrm{T}}\left[\begin{array}{l} 1 \\ 0 \\ 1 \end{array}\right]=\left[\begin{array}{l} 5 \\ 2 \\ 2 \end{array}\right], \mathrm{A}^{\mathrm{T}}\left[\begin{array}{l} 0 \\ 0 \\ 1 \end{array}\right]=\left[\begin{array}{l} 3 \\ 1 \\ 1 \end{array}\right], \mathrm{A}\left[\begin{array}{l} 1 \\ 0 \\ 1 \end{array}\right]=\left[\begin{array}{l} 3 \\ 4 \\ 4 \end{array}\right] \text { and } \mathrm{A}\left[\begin{array}{l} 0 \\ 0 \\ 1 \end{array}\right]=\left[\begin{array}{l} 1 \\ 3 \\ 1 \end{array}\right] . $
If $\operatorname{det}(A)=1$, then $\operatorname{det}\left(\operatorname{adj}\left(A^2+A\right)\right)$ is equal to:
JEE Mains
2026
MCQ
Consider the system of linear equations in $x, y, z$ :
$ \begin{aligned} & x+2 y+t z=0 \\ & 6 x+y+5 t z=0 \\ & 3 x+t^2 y+f(t) z=0 \end{aligned} $
where $f: \mathbb{R} \rightarrow \mathbb{R}$ is a differentiable function. If this system has infinitely many solutions for all $t \in \mathbb{R}$, then $f$
JEE Mains
2026
MCQ
If the system of equations :
$ \begin{aligned} & x+y+z=5 \\ & x+2 y+3 z=9 \\ & x+3 y+\lambda z=\mu \end{aligned} $
has infinitely many solutions, then the value of $\lambda+\mu$ is :
JEE Mains
2026
MCQ
Let $A=\left[\begin{array}{ccc}1 & 2 & 7 \\ 4 & -2 & 8 \\ 3 & 8 & -7\end{array}\right]$ and $\operatorname{det}(A-\alpha I)=0$, where $\alpha$ is a real number. If the largest possible value of $\alpha$ is $p$, then the circle $(x-p)^2+(y-2 p)^2=320$, intersects the co-ordinate axes at
JEE Mains
2026
MCQ
Let $\mathrm{S}=\left\{\mathrm{A}=\left[\begin{array}{ll}a & b \\ c & d\end{array}\right]: a, b, c, d \in\{0,1,2,3,4\}\right.$ and $\left.\mathrm{A}^2-4 \mathrm{~A}+3 \mathrm{I}=0\right\}$ be a set of $2 \times 2$ matrices. Then the number of matrices in S , for which the sum of the diagonal elements is equal to 4 , is :
JEE Mains
2026
MCQ
Let $A=\left[\begin{array}{ccc}1 & 1 & 2 \\ -2 & 0 & 1 \\ 1 & 3 & 5\end{array}\right]$. Then the sum of all elements of the matrix $\operatorname{adj}\left(\operatorname{adj}\left(2(\operatorname{adj} \mathrm{~A})^{-1}\right)\right)$ is equal to:
JEE Mains
2026
MCQ
If the system of equations
$x + 5y + 6z = 4$
$2x + 3y + 4z = 7$
$x + 6y + az = b$
has infinitely many solutions, then the point $(a, b)$ lies on the line
JEE Mains
2026
MCQ
Let $\alpha, \beta \in \mathbb{R}$ be such that the system of linear equations
$ \begin{aligned} x + 2y + z &= 5 \\ 2x + y + \alpha z &= 5 \\ 8x + 4y + \beta z &= 18 \end{aligned} $
has no solution. Then $\frac{\beta}{\alpha}$ is equal to :
JEE Mains
2026
MCQ
Let $A = \begin{bmatrix} 1 & 2 \\ 1 & \alpha \end{bmatrix}$ and $B = \begin{bmatrix} 3 & 3 \\ \beta & 2 \end{bmatrix}$. If $A^2 - 4A + I = O$ and $B^2 - 5B - 6I = O$, then among the two statements:
(S1) : $[(B-A)(B+A)]^T = \begin{bmatrix} 13 & 15 \\ 7 & 10 \end{bmatrix}$
and
(S2) : $\det(\mathrm{adj}(A+B)) = -5$
JEE Mains
2025
MCQ
Let α be a solution of $x^2 + x + 1 = 0$, and for some a and b in
$R, \begin{bmatrix} 4 & a & b \end{bmatrix} \begin{bmatrix} 1 & 16 & 13 \\ -1 & -1 & 2 \\ -2 & -14 & -8 \end{bmatrix} = \begin{bmatrix} 0 & 0 & 0 \end{bmatrix}$. If $\frac{4}{\alpha^4} + \frac{m}{\alpha^a} + \frac{n}{\alpha^b} = 3$, then m + n is equal to _______
JEE Mains
2025
MCQ
Let $ A = \begin{bmatrix} 2 & 2+p & 2+p+q \\ 4 & 6+2p & 8+3p+2q \\ 6 & 12+3p & 20+6p+3q \end{bmatrix} $.
If $ \det(\text{adj}(\text{adj}(3A))) = 2^m \cdot 3^n $, $ m, n \in \mathbb{N} $, then $ m + n $ is equal to
JEE Mains
2025
MCQ
Let the system of equations
x + 5y - z = 1
4x + 3y - 3z = 7
24x + y + λz = μ
λ, μ ∈ ℝ, have infinitely many solutions. Then the number of the solutions of this system,
if x, y, z are integers and satisfy 7 ≤ x + y + z ≤ 77, is :
JEE Mains
2025
MCQ
Let $A$ be a $3 \times 3$ matrix such that $|\operatorname{adj}(\operatorname{adj}(\operatorname{adj} \mathrm{A}))|=81$.
If $S=\left\{n \in \mathbb{Z}:(|\operatorname{adj}(\operatorname{adj} A)|)^{\frac{(n-1)^2}{2}}=|A|^{\left(3 n^2-5 n-4\right)}\right\}$, then $\sum_\limits{n \in S}\left|A^{\left(n^2+n\right)}\right|$ is equal to :
JEE Mains
2025
MCQ
Let the system of equations :
$ \begin{aligned} & 2 x+3 y+5 z=9 \\ & 7 x+3 y-2 z=8 \\ & 12 x+3 y-(4+\lambda) z=16-\mu \end{aligned}$
have infinitely many solutions. Then the radius of the circle centred at $(\lambda, \mu)$ and touching the line $4 x=3 y$ is :
JEE Mains
2025
MCQ
Let the matrix $A=\left[\begin{array}{lll}1 & 0 & 0 \\ 1 & 0 & 1 \\ 0 & 1 & 0\end{array}\right]$ satisfy $A^n=A^{n-2}+A^2-I$ for $n \geqslant 3$. Then the sum of all the elements of $\mathrm{A}^{50}$ is :
JEE Mains
2025
MCQ
Let $A$ be a matrix of order $3 \times 3$ and $|A|=5$. If $|2 \operatorname{adj}(3 A \operatorname{adj}(2 A))|=2^\alpha \cdot 3^\beta \cdot 5^\gamma, \alpha, \beta, \gamma \in N$, then $\alpha+\beta+\gamma$ is equal to
JEE Mains
2025
MCQ
If the system of equations
$ \begin{aligned} & 2 x+\lambda y+3 z=5 \\ & 3 x+2 y-z=7 \\ & 4 x+5 y+\mu z=9 \end{aligned} $
has infinitely many solutions, then $\left(\lambda^2+\mu^2\right)$ is equal to :
JEE Mains
2025
MCQ
Let $A$ be a $3 \times 3$ real matrix such that $A^2(A-2 I)-4(A-I)=O$, where $I$ and $O$ are the identity and null matrices, respectively. If $A^5=\alpha A^2+\beta A+\gamma I$, where $\alpha, \beta$, and $\gamma$ are real constants, then $\alpha+\beta+\gamma$ is equal to :
JEE Mains
2025
MCQ
Let $\mathrm{A}=\left[\begin{array}{cc}\alpha & -1 \\ 6 & \beta\end{array}\right], \alpha>0$, such that $\operatorname{det}(\mathrm{A})=0$ and $\alpha+\beta=1$. If I denotes $2 \times 2$ identity matrix, then the matrix $(I+A)^8$ is :
JEE Mains
2025
MCQ
Let $a \in R$ and $A$ be a matrix of order $3 \times 3$ such that $\operatorname{det}(A)=-4$ and $A+I=\left[\begin{array}{lll}1 & a & 1 \\ 2 & 1 & 0 \\ a & 1 & 2\end{array}\right]$, where $I$ is the identity matrix of order $3 \times 3$. If $\operatorname{det}((a+1) \operatorname{adj}((a-1) A))$ is $2^{\mathrm{m}} 3^{\mathrm{n}}, \mathrm{m}$, $\mathrm{n} \in\{0,1,2, \ldots, 20\}$, then $\mathrm{m}+\mathrm{n}$ is equal to :
JEE Mains
2025
MCQ
If the system of linear equations
$ \begin{aligned} & 3 x+y+\beta z=3 \\ & 2 x+\alpha y-z=-3 \\ & x+2 y+z=4 \end{aligned} $
has infinitely many solutions, then the value of $22 \beta-9 \alpha$ is :
JEE Mains
2025
MCQ
Let $A = [a_{ij}]$ be a $2 \times 2$ matrix such that $a_{ij} \in \{0, 1\}$ for all $i$ and $j$. Let the random variable $X$ denote the possible values of the determinant of the matrix $A$. Then, the variance of $X$ is:
JEE Mains
2025
MCQ
Let $ \alpha, \beta \ (\alpha \neq \beta) $ be the values of $ m $, for which the equations $ x+y+z=1 $, $ x+2y+4z=m $ and $ x+4y+10z=m^2 $ have infinitely many solutions. Then the value of $ \sum\limits_{n=1}^{10} (n^{\alpha}+n^{\beta}) $ is equal to :
JEE Mains
2025
MCQ
Let $\mathrm{A}=\left[a_{i j}\right]$ be a matrix of order $3 \times 3$, with $a_{i j}=(\sqrt{2})^{i+j}$. If the sum of all the elements in the third row of $A^2$ is $\alpha+\beta \sqrt{2}, \alpha, \beta \in \mathbf{Z}$, then $\alpha+\beta$ is equal to :
JEE Mains
2025
MCQ
Let $ A = \begin{bmatrix} a_{ij} \end{bmatrix} = \begin{bmatrix} \log_5 128 & \log_4 5 \\ \log_5 8 & \log_4 25 \end{bmatrix} $. If $ A_{ij} $ is the cofactor of $ a_{ij} $, $ C_{ij} = \sum\limits_{k=1}^{2} a_{ik} A_{jk} , 1 \leq i, j \leq 2 $, and $ C=[C_{ij}] $, then $ 8|C| $ is equal to :
JEE Mains
2025
MCQ
Let M and m respectively be the maximum and the minimum values of
$f(x)=\left|\begin{array}{ccc}1+\sin ^2 x & \cos ^2 x & 4 \sin 4 x \\ \sin ^2 x & 1+\cos ^2 x & 4 \sin 4 x \\ \sin ^2 x & \cos ^2 x & 1+4 \sin 4 x\end{array}\right|, x \in R$
Then $ M^4 - m^4 $ is equal to :
JEE Mains
2025
MCQ
Let $\mathrm{A}=\left[\begin{array}{cc}\frac{1}{\sqrt{2}} & -2 \\ 0 & 1\end{array}\right]$ and $\mathrm{P}=\left[\begin{array}{cc}\cos \theta & -\sin \theta \\ \sin \theta & \cos \theta\end{array}\right], \theta>0$. If $\mathrm{B}=\mathrm{PAP}{ }^{\top}, \mathrm{C}=\mathrm{P}^{\top} \mathrm{B}^{10} \mathrm{P}$ and the sum of the diagonal elements of $C$ is $\frac{m}{n}$, where $\operatorname{gcd}(m, n)=1$, then $m+n$ is :
JEE Mains
2025
MCQ
For some $a, b,$ let $f(x)=\left|\begin{array}{ccc}\mathrm{a}+\frac{\sin x}{x} & 1 & \mathrm{~b} \\ \mathrm{a} & 1+\frac{\sin x}{x} & \mathrm{~b} \\ \mathrm{a} & 1 & \mathrm{~b}+\frac{\sin x}{x}\end{array}\right|, x \neq 0, \lim \limits_{x \rightarrow 0} f(x)=\lambda+\mu \mathrm{a}+\nu \mathrm{b}.$ Then $(\lambda+\mu+v)^2$ is equal to :
JEE Mains
2025
MCQ
If the system of equations
$
\begin{aligned}
& x+2 y-3 z=2 \\
& 2 x+\lambda y+5 z=5 \\
& 14 x+3 y+\mu z=33
\end{aligned}
$
has infinitely many solutions, then $\lambda+\mu$ is equal to :
JEE Mains
2025
MCQ
If the system of equations
$\begin{aligned}
& 2 x-y+z=4 \\
& 5 x+\lambda y+3 z=12 \\
& 100 x-47 y+\mu z=212
\end{aligned}$
has infinitely many solutions, then $\mu-2 \lambda$ is equal to
JEE Mains
2025
MCQ
The system of equations
$\begin{aligned}
& x+y+z=6, \\
& x+2 y+5 z=9, \\
& x+5 y+\lambda z=\mu,
\end{aligned}$
has no solution if
JEE Mains
2025
MCQ
Let $A=\left[a_{i j}\right]$ be a $3 \times 3$ matrix such that $A\left[\begin{array}{l}0 \\ 1 \\ 0\end{array}\right]=\left[\begin{array}{l}0 \\ 0 \\ 1\end{array}\right], A\left[\begin{array}{l}4 \\ 1 \\ 3\end{array}\right]=\left[\begin{array}{l}0 \\ 1 \\ 0\end{array}\right]$ and $A\left[\begin{array}{l}2 \\ 1 \\ 2\end{array}\right]=\left[\begin{array}{l}1 \\ 0 \\ 0\end{array}\right]$, then $a_{23}$ equals :
JEE Mains
2025
MCQ
If the system of equations
$
\begin{aligned}
& (\lambda-1) x+(\lambda-4) y+\lambda z=5 \\
& \lambda x+(\lambda-1) y+(\lambda-4) z=7 \\
& (\lambda+1) x+(\lambda+2) y-(\lambda+2) z=9
\end{aligned}$
has infinitely many solutions, then $\lambda^2+\lambda$ is equal to
JEE Mains
2025
MCQ
If $\mathrm{A}, \mathrm{B}, \operatorname{and}\left(\operatorname{adj}\left(\mathrm{A}^{-1}\right)+\operatorname{adj}\left(\mathrm{B}^{-1}\right)\right)$ are non-singular matrices of same order, then the inverse of $A\left(\operatorname{adj}\left(A^{-1}\right)+\operatorname{adj}\left(B^{-1}\right)\right)^{-1} B$, is equal to
JEE Mains
2025
MCQ
If the system of linear equations :
$\begin{aligned}
& x+y+2 z=6 \\
& 2 x+3 y+\mathrm{az}=\mathrm{a}+1 \\
& -x-3 y+\mathrm{b} z=2 \mathrm{~b}
\end{aligned}$
where $a, b \in \mathbf{R}$, has infinitely many solutions, then $7 a+3 b$ is equal to :
JEE Mains
2025
MCQ
For a $3 \times 3$ matrix $M$, let trace $(M)$ denote the sum of all the diagonal elements of $M$. Let $A$ be a $3 \times 3$ matrix such that $|A|=\frac{1}{2}$ and trace $(A)=3$. If $B=\operatorname{adj}(\operatorname{adj}(2 A))$, then the value of $|B|+$ trace $(B)$ equals :
JEE Mains
2024
MCQ
Let $B=\left[\begin{array}{ll}1 & 3 \\ 1 & 5\end{array}\right]$ and $A$ be a $2 \times 2$ matrix such that $A B^{-1}=A^{-1}$. If $B C B^{-1}=A$ and $C^4+\alpha C^2+\beta I=O$, then $2 \beta-\alpha$ is equal to
JEE Mains
2024
MCQ
Let $\lambda, \mu \in \mathbf{R}$. If the system of equations
$\begin{aligned}
& 3 x+5 y+\lambda z=3 \\
& 7 x+11 y-9 z=2 \\
& 97 x+155 y-189 z=\mu
\end{aligned}$
has infinitely many solutions, then $\mu+2 \lambda$ is equal to :
JEE Mains
2024
MCQ
If $\alpha \neq \mathrm{a}, \beta \neq \mathrm{b}, \gamma \neq \mathrm{c}$ and $\left|\begin{array}{lll}\alpha & \mathrm{b} & \mathrm{c} \\ \mathrm{a} & \beta & \mathrm{c} \\ \mathrm{a} & \mathrm{b} & \gamma\end{array}\right|=0$, then $\frac{\mathrm{a}}{\alpha-\mathrm{a}}+\frac{\mathrm{b}}{\beta-\mathrm{b}}+\frac{\gamma}{\gamma-\mathrm{c}}$ is equal to :
JEE Mains
2024
MCQ
If the system of equations $x+4 y-z=\lambda, 7 x+9 y+\mu z=-3,5 x+y+2 z=-1$ has infinitely many solutions, then $(2 \mu+3 \lambda)$ is equal to :
JEE Mains
2024
MCQ
Let $A=\left[\begin{array}{lll}2 & a & 0 \\ 1 & 3 & 1 \\ 0 & 5 & b\end{array}\right]$. If $A^3=4 A^2-A-21 I$, where $I$ is the identity matrix of order $3 \times 3$, then $2 a+3 b$ is equal to
JEE Mains
2024
MCQ
If $A$ is a square matrix of order 3 such that $\operatorname{det}(A)=3$ and $\operatorname{det}\left(\operatorname{adj}\left(-4 \operatorname{adj}\left(-3 \operatorname{adj}\left(3 \operatorname{adj}\left((2 \mathrm{~A})^{-1}\right)\right)\right)\right)\right)=2^{\mathrm{m}} 3^{\mathrm{n}}$, then $\mathrm{m}+2 \mathrm{n}$ is equal to :
JEE Mains
2024
MCQ
For $\alpha, \beta \in \mathbb{R}$ and a natural number $n$, let $A_r=\left|\begin{array}{ccc}r & 1 & \frac{n^2}{2}+\alpha \\ 2 r & 2 & n^2-\beta \\ 3 r-2 & 3 & \frac{n(3 n-1)}{2}\end{array}\right|$. Then $2 A_{10}-A_8$ is
JEE Mains
2024
MCQ
The values of $m, n$, for which the system of equations
$\begin{aligned}
& x+y+z=4, \\
& 2 x+5 y+5 z=17, \\
& x+2 y+\mathrm{m} z=\mathrm{n}
\end{aligned}$
has infinitely many solutions, satisfy the equation :
JEE Mains
2024
MCQ
Let $\alpha \beta \neq 0$ and $A=\left[\begin{array}{rrr}\beta & \alpha & 3 \\ \alpha & \alpha & \beta \\ -\beta & \alpha & 2 \alpha\end{array}\right]$. If $B=\left[\begin{array}{rrr}3 \alpha & -9 & 3 \alpha \\ -\alpha & 7 & -2 \alpha \\ -2 \alpha & 5 & -2 \beta\end{array}\right]$ is the matrix of cofactors of the elements of $A$, then $\operatorname{det}(A B)$ is equal to :
JEE Mains
2024
MCQ
Let A and B be two square matrices of order 3 such that $\mathrm{|A|=3}$ and $\mathrm{|B|=2}$. Then $|\mathrm{A}^{\mathrm{T}} \mathrm{A}(\operatorname{adj}(2 \mathrm{~A}))^{-1}(\operatorname{adj}(4 \mathrm{~B}))(\operatorname{adj}(\mathrm{AB}))^{-1} \mathrm{AA}^{\mathrm{T}}|$ is equal to :
JEE Mains
2024
MCQ
If the system of equations
$\begin{array}{r}
11 x+y+\lambda z=-5 \\
2 x+3 y+5 z=3 \\
8 x-19 y-39 z=\mu
\end{array}$
has infinitely many solutions, then $\lambda^4-\mu$ is equal to :
JEE Mains
2024
MCQ
Let $A=\left[\begin{array}{ll}1 & 2 \\ 0 & 1\end{array}\right]$ and $B=I+\operatorname{adj}(A)+(\operatorname{adj} A)^2+\ldots+(\operatorname{adj} A)^{10}$.
Then, the sum of all the elements of the matrix $B$ is:
JEE Mains
2024
MCQ
Let $\alpha \in(0, \infty)$ and $A=\left[\begin{array}{lll}1 & 2 & \alpha \\ 1 & 0 & 1 \\ 0 & 1 & 2\end{array}\right]$. If $\operatorname{det}\left(\operatorname{adj}\left(2 A-A^T\right) \cdot \operatorname{adj}\left(A-2 A^T\right)\right)=2^8$, then $(\operatorname{det}(A))^2$ is equal to:
JEE Mains
2024
MCQ
If the system of equations
$\begin{aligned}
& x+(\sqrt{2} \sin \alpha) y+(\sqrt{2} \cos \alpha) z=0 \\
& x+(\cos \alpha) y+(\sin \alpha) z=0 \\
& x+(\sin \alpha) y-(\cos \alpha) z=0
\end{aligned}$
has a non-trivial solution, then $\alpha \in\left(0, \frac{\pi}{2}\right)$ is equal to :
JEE Mains
2024
MCQ
Let the system of equations $x+2 y+3 z=5,2 x+3 y+z=9,4 x+3 y+\lambda z=\mu$ have infinite number of solutions. Then $\lambda+2 \mu$ is equal to :
JEE Mains
2024
MCQ
If $\mathrm{A}=\left[\begin{array}{cc}\sqrt{2} & 1 \\ -1 & \sqrt{2}\end{array}\right], \mathrm{B}=\left[\begin{array}{ll}1 & 0 \\ 1 & 1\end{array}\right], \mathrm{C}=\mathrm{ABA}^{\mathrm{T}}$ and $\mathrm{X}=\mathrm{A}^{\mathrm{T}} \mathrm{C}^2 \mathrm{~A}$, then $\operatorname{det} \mathrm{X}$ is equal to :
JEE Mains
2024
MCQ
If the system of equations
$
\begin{aligned}
& 2 x+3 y-z=5 \\\\
& x+\alpha y+3 z=-4 \\\\
& 3 x-y+\beta z=7
\end{aligned}
$
has infinitely many solutions, then $13 \alpha \beta$ is equal to :
JEE Mains
2024
MCQ
Let $A$ be a $3 \times 3$ real matrix such that
$A\left(\begin{array}{l}
1 \\
0 \\
1
\end{array}\right)=2\left(\begin{array}{l}
1 \\
0 \\
1
\end{array}\right), A\left(\begin{array}{l}
-1 \\
0 \\
1
\end{array}\right)=4\left(\begin{array}{l}
-1 \\
0 \\
1
\end{array}\right), A\left(\begin{array}{l}
0 \\
1 \\
0
\end{array}\right)=2\left(\begin{array}{l}
0 \\
1 \\
0
\end{array}\right) \text {. }$
Then, the system $(A-3 I)\left(\begin{array}{l}x \\ y \\ z\end{array}\right)=\left(\begin{array}{l}1 \\ 2 \\ 3\end{array}\right)$ has :
JEE Mains
2024
MCQ
If the system of linear equations
$\begin{aligned}
& x-2 y+z=-4 \\
& 2 x+\alpha y+3 z=5 \\
& 3 x-y+\beta z=3
\end{aligned}$
has infinitely many solutions, then $12 \alpha+13 \beta$ is equal to
JEE Mains
2024
MCQ
Let $R=\left(\begin{array}{ccc}x & 0 & 0 \\ 0 & y & 0 \\ 0 & 0 & z\end{array}\right)$ be a non-zero $3 \times 3$ matrix, where $x \sin \theta=y \sin \left(\theta+\frac{2 \pi}{3}\right)=z \sin \left(\theta+\frac{4 \pi}{3}\right) \neq 0, \theta \in(0,2 \pi)$. For a square matrix $M$, let trace $(M)$ denote the sum of all the diagonal entries of $M$. Then, among the statements:
(I) Trace $(R)=0$
(II) If trace $(\operatorname{adj}(\operatorname{adj}(R))=0$, then $R$ has exactly one non-zero entry.
JEE Mains
2024
MCQ
Consider the system of linear equations $x+y+z=5, x+2 y+\lambda^2 z=9, x+3 y+\lambda z=\mu$, where $\lambda, \mu \in \mathbb{R}$. Then, which of the following statement is NOT correct?
JEE Mains
2024
MCQ
Consider the system of linear equations $x+y+z=4 \mu, x+2 y+2 \lambda z=10 \mu, x+3 y+4 \lambda^2 z=\mu^2+15$ where $\lambda, \mu \in \mathbf{R}$. Which one of the following statements is NOT correct ?
JEE Mains
2024
MCQ
Let $A=\left[\begin{array}{ccc}2 & 1 & 2 \\ 6 & 2 & 11 \\ 3 & 3 & 2\end{array}\right]$ and $P=\left[\begin{array}{lll}1 & 2 & 0 \\ 5 & 0 & 2 \\ 7 & 1 & 5\end{array}\right]$. The sum of the prime factors of $\left|P^{-1} A P-2 I\right|$ is equal to
JEE Mains
2024
MCQ
$\text { Let } A=\left[\begin{array}{lll}
1 & 0 & 0 \\
0 & \alpha & \beta \\
0 & \beta & \alpha
\end{array}\right] \text { and }|2 \mathrm{~A}|^3=2^{21} \text { where } \alpha, \beta \in Z \text {, Then a value of } \alpha \text { is }$
JEE Mains
2024
MCQ
Let $\mathrm{A}$ be a square matrix such that $\mathrm{AA}^{\mathrm{T}}=\mathrm{I}$. Then $\frac{1}{2} A\left[\left(A+A^T\right)^2+\left(A-A^T\right)^2\right]$ is equal to
JEE Mains
2024
MCQ
The values of $\alpha$, for which $\left|\begin{array}{ccc}1 & \frac{3}{2} & \alpha+\frac{3}{2} \\ 1 & \frac{1}{3} & \alpha+\frac{1}{3} \\ 2 \alpha+3 & 3 \alpha+1 & 0\end{array}\right|=0$, lie in the interval
JEE Mains
2024
MCQ
Consider the matrix $f(x)=\left[\begin{array}{ccc}\cos x & -\sin x & 0 \\ \sin x & \cos x & 0 \\ 0 & 0 & 1\end{array}\right]$.
Given below are two statements :
Statement I : $ f(-x)$ is the inverse of the matrix $f(x)$.
Statement II : $f(x) f(y)=f(x+y)$.
In the light of the above statements, choose the correct answer from the options given below :
JEE Mains
2023
MCQ
Let the determinant of a square matrix A of order $m$ be $m-n$, where $m$ and $n$
satisfy $4 m+n=22$ and $17 m+4 n=93$.
If $\operatorname{det}(n \operatorname{adj}(\operatorname{adj}(m A)))=3^{a} 5^{b} 6^{c}$ then $a+b+c$ is equal to :
JEE Mains
2023
MCQ
Let for $A = \left[ {\matrix{
1 & 2 & 3 \cr
\alpha & 3 & 1 \cr
1 & 1 & 2 \cr
} } \right],|A| = 2$. If $\mathrm{|2\,adj\,(2\,adj\,(2A))| = {32^n}}$, then $3n + \alpha $ is equal to
JEE Mains
2023
MCQ
If the system of equations
$2 x+y-z=5$
$2 x-5 y+\lambda z=\mu$
$x+2 y-5 z=7$
has infinitely many solutions, then $(\lambda+\mu)^{2}+(\lambda-\mu)^{2}$ is equal to
JEE Mains
2023
MCQ
For the system of linear equations
$2 x+4 y+2 a z=b$
$x+2 y+3 z=4$
$2 x-5 y+2 z=8$
which of the following is NOT correct?
JEE Mains
2023
MCQ
Let $B=\left[\begin{array}{lll}1 & 3 & \alpha \\ 1 & 2 & 3 \\ \alpha & \alpha & 4\end{array}\right], \alpha > 2$ be the adjoint of a matrix $A$ and $|A|=2$. Then
$\left[\begin{array}{ccc}\alpha & -2 \alpha & \alpha\end{array}\right] B\left[\begin{array}{c}\alpha \\ -2 \alpha \\ \alpha\end{array}\right]$ is equal to :
JEE Mains
2023
MCQ
The number of symmetric matrices of order 3, with all the entries from the set $\{0,1,2,3,4,5,6,7,8,9\}$ is :
JEE Mains
2023
MCQ
Let $A=\left[\begin{array}{cc}1 & \frac{1}{51} \\ 0 & 1\end{array}\right]$. If $\mathrm{B}=\left[\begin{array}{cc}1 & 2 \\ -1 & -1\end{array}\right] A\left[\begin{array}{cc}-1 & -2 \\ 1 & 1\end{array}\right]$, then the sum of all the elements of the matrix $\sum_\limits{n=1}^{50} B^{n}$ is equal to
JEE Mains
2023
MCQ
If the system of linear equations
$
\begin{aligned}
& 7 x+11 y+\alpha z=13 \\\\
& 5 x+4 y+7 z=\beta \\\\
& 175 x+194 y+57 z=361
\end{aligned}
$
has infinitely many solutions, then $\alpha+\beta+2$ is equal to :
JEE Mains
2023
MCQ
$\left|\begin{array}{ccc}x+1 & x & x \\ x & x+\lambda & x \\ x & x & x+\lambda^{2}\end{array}\right|=\frac{9}{8}(103 x+81)$, then $\lambda, \frac{\lambda}{3}$ are the roots of the equation :
JEE Mains
2023
MCQ
Let $\mathrm{A}$ be a $2 \times 2$ matrix with real entries such that $\mathrm{A}'=\alpha \mathrm{A}+\mathrm{I}$, where $\alpha \in \mathbb{R}-\{-1,1\}$. If $\operatorname{det}\left(A^{2}-A\right)=4$, then the sum of all possible values of $\alpha$ is equal to :
JEE Mains
2023
MCQ
If $\mathrm{A}=\frac{1}{5 ! 6 ! 7 !}\left[\begin{array}{ccc}5 ! & 6 ! & 7 ! \\ 6 ! & 7 ! & 8 ! \\ 7 ! & 8 ! & 9 !\end{array}\right]$, then $|\operatorname{adj}(\operatorname{adj}(2 \mathrm{~A}))|$ is equal to :
JEE Mains
2023
MCQ
If A is a 3 $\times$ 3 matrix and $|A| = 2$, then $|3\,adj\,(|3A|{A^2})|$ is equal to :
JEE Mains
2023
MCQ
For the system of linear equations
$2x - y + 3z = 5$
$3x + 2y - z = 7$
$4x + 5y + \alpha z = \beta $,
which of the following is NOT correct?
JEE Mains
2023
MCQ
If $A=\left[\begin{array}{cc}1 & 5 \\ \lambda & 10\end{array}\right], \mathrm{A}^{-1}=\alpha \mathrm{A}+\beta \mathrm{I}$ and $\alpha+\beta=-2$, then $4 \alpha^{2}+\beta^{2}+\lambda^{2}$ is equal to :
JEE Mains
2023
MCQ
Let S be the set of all values of $\theta \in[-\pi, \pi]$ for which the system of linear equations
$x+y+\sqrt{3} z=0$
$-x+(\tan \theta) y+\sqrt{7} z=0$
$x+y+(\tan \theta) z=0$
has non-trivial solution. Then $\frac{120}{\pi} \sum_\limits{\theta \in \mathrm{s}} \theta$ is equal to :
JEE Mains
2023
MCQ
Let $A=\left[\begin{array}{ccc}2 & 1 & 0 \\ 1 & 2 & -1 \\ 0 & -1 & 2\end{array}\right]$. If $|\operatorname{adj}(\operatorname{adj}(\operatorname{adj} 2 A))|=(16)^{n}$, then $n$ is equal to :
JEE Mains
2023
MCQ
Let $P=\left[\begin{array}{cc}\frac{\sqrt{3}}{2} & \frac{1}{2} \\ -\frac{1}{2} & \frac{\sqrt{3}}{2}\end{array}\right], A=\left[\begin{array}{ll}1 & 1 \\ 0 & 1\end{array}\right]$ and $Q=P A P^{T}$. If $P^{T} Q^{2007} P=\left[\begin{array}{ll}a & b \\ c & d\end{array}\right]$, then $2 a+b-3 c-4 d$ equal to :
JEE Mains
2023
MCQ
Let $P$ be a square matrix such that $P^{2}=I-P$. For $\alpha, \beta, \gamma, \delta \in \mathbb{N}$, if $P^{\alpha}+P^{\beta}=\gamma I-29 P$ and $P^{\alpha}-P^{\beta}=\delta I-13 P$, then $\alpha+\beta+\gamma-\delta$ is equal to :
JEE Mains
2023
MCQ
For the system of equations
$x+y+z=6$
$x+2 y+\alpha z=10$
$x+3 y+5 z=\beta$, which one of the following is NOT true?
JEE Mains
2023
MCQ
If the system of equations
$x+y+a z=b$
$2 x+5 y+2 z=6$
$x+2 y+3 z=3$
has infinitely many solutions, then $2 a+3 b$ is equal to :
JEE Mains
2023
MCQ
Let $\mathrm{A}=\left[\mathrm{a}_{\mathrm{ij}}\right]_{2 \times 2}$, where $\mathrm{a}_{\mathrm{ij}} \neq 0$ for all $\mathrm{i}, \mathrm{j}$ and $\mathrm{A}^{2}=\mathrm{I}$. Let a be the sum of all diagonal elements of $\mathrm{A}$ and $\mathrm{b}=|\mathrm{A}|$. Then $3 a^{2}+4 b^{2}$ is equal to :
JEE Mains
2023
MCQ
For the system of linear equations $\alpha x+y+z=1,x+\alpha y+z=1,x+y+\alpha z=\beta$, which one of the following statements is NOT correct?
JEE Mains
2023
MCQ
If $A = {1 \over 2}\left[ {\matrix{
1 & {\sqrt 3 } \cr
{ - \sqrt 3 } & 1 \cr
} } \right]$, then :
JEE Mains
2023
MCQ
Let $S$ denote the set of all real values of $\lambda$ such that the system of equations
$\lambda x+y+z=1$
$x+\lambda y+z=1$
$x+y+\lambda z=1$
is inconsistent, then $\sum_\limits{\lambda \in S}\left(|\lambda|^{2}+|\lambda|\right)$ is equal to
JEE Mains
2023
MCQ
For the system of linear equations
$x+y+z=6$
$\alpha x+\beta y+7 z=3$
$x+2 y+3 z=14$
which of the following is NOT true ?
JEE Mains
2023
MCQ
Let $A = \left( {\matrix{
1 & 0 & 0 \cr
0 & 4 & { - 1} \cr
0 & {12} & { - 3} \cr
} } \right)$. Then the sum of the diagonal elements of the matrix ${(A + I)^{11}}$ is equal to :
JEE Mains
2023
MCQ
For $\alpha, \beta \in \mathbb{R}$, suppose the system of linear equations
$
\begin{aligned}
& x-y+z=5 \\
& 2 x+2 y+\alpha z=8 \\
& 3 x-y+4 z=\beta
\end{aligned}
$
has infinitely many solutions. Then $\alpha$ and $\beta$ are the roots of :
JEE Mains
2023
MCQ
If $P$ is a $3 \times 3$ real matrix such that $P^T=a P+(a-1) I$, where $a>1$, then :
JEE Mains
2023
MCQ
Let the system of linear equations
$x+y+kz=2$
$2x+3y-z=1$
$3x+4y+2z=k$
have infinitely many solutions. Then the system
$(k+1)x+(2k-1)y=7$
$(2k+1)x+(k+5)y=10$
has :
JEE Mains
2023
MCQ
Let $A=\left(\begin{array}{cc}\mathrm{m} & \mathrm{n} \\ \mathrm{p} & \mathrm{q}\end{array}\right), \mathrm{d}=|\mathrm{A}| \neq 0$ and $\mathrm{|A-d(A d j A)|=0}$. Then
JEE Mains
2023
MCQ
The set of all values of $\mathrm{t\in \mathbb{R}}$, for which the matrix
$\left[ {\matrix{
{{e^t}} & {{e^{ - t}}(\sin t - 2\cos t)} & {{e^{ - t}}( - 2\sin t - \cos t)} \cr
{{e^t}} & {{e^{ - t}}(2\sin t + \cos t)} & {{e^{ - t}}(\sin t - 2\cos t)} \cr
{{e^t}} & {{e^{ - t}}\cos t} & {{e^{ - t}}\sin t} \cr
} } \right]$ is invertible, is :
JEE Mains
2023
MCQ
Let $\alpha$ and $\beta$ be real numbers. Consider a 3 $\times$ 3 matrix A such that $A^2=3A+\alpha I$. If $A^4=21A+\beta I$, then
JEE Mains
2023
MCQ
Consider the following system of equations
$\alpha x+2y+z=1$
$2\alpha x+3y+z=1$
$3x+\alpha y+2z=\beta$
for some $\alpha,\beta\in \mathbb{R}$. Then which of the following is NOT correct.
JEE Mains
2023
MCQ
Let A, B, C be 3 $\times$ 3 matrices such that A is symmetric and B and C are skew-symmetric. Consider the statements
(S1) A$^{13}$ B$^{26}$ $-$ B$^{26}$ A$^{13}$ is symmetric
(S2) A$^{26}$ C$^{13}$ $-$ C$^{13}$ A$^{26}$ is symmetric
Then,
JEE Mains
2023
MCQ
Let $A = \left[ {\matrix{
{{1 \over {\sqrt {10} }}} & {{3 \over {\sqrt {10} }}} \cr
{{{ - 3} \over {\sqrt {10} }}} & {{1 \over {\sqrt {10} }}} \cr
} } \right]$ and $B = \left[ {\matrix{
1 & { - i} \cr
0 & 1 \cr
} } \right]$, where $i = \sqrt { - 1} $. If $\mathrm{M=A^T B A}$, then the inverse of the matrix $\mathrm{AM^{2023}A^T}$ is
JEE Mains
2023
MCQ
Let $x,y,z > 1$ and $A = \left[ {\matrix{
1 & {{{\log }_x}y} & {{{\log }_x}z} \cr
{{{\log }_y}x} & 2 & {{{\log }_y}z} \cr
{{{\log }_z}x} & {{{\log }_z}y} & 3 \cr
} } \right]$. Then $\mathrm{|adj~(adj~A^2)|}$ is equal to
JEE Mains
2023
MCQ
Let S$_1$ and S$_2$ be respectively the sets of all $a \in \mathbb{R} - \{ 0\} $ for which the system of linear equations
$ax + 2ay - 3az = 1$
$(2a + 1)x + (2a + 3)y + (a + 1)z = 2$
$(3a + 5)x + (a + 5)y + (a + 2)z = 3$
has unique solution and infinitely many solutions. Then
JEE Mains
2023
MCQ
Let A be a 3 $\times$ 3 matrix such that $\mathrm{|adj(adj(adj~A))|=12^4}$. Then $\mathrm{|A^{-1}~adj~A|}$ is equal to
JEE Mains
2023
MCQ
If the system of equations
$x+2y+3z=3$
$4x+3y-4z=4$
$8x+4y-\lambda z=9+\mu$
has infinitely many solutions, then the ordered pair ($\lambda,\mu$) is equal to :
JEE Mains
2023
MCQ
If A and B are two non-zero n $\times$ n matrices such that $\mathrm{A^2+B=A^2B}$, then :
JEE Mains
2023
MCQ
Let $\alpha$ be a root of the equation $(a - c){x^2} + (b - a)x + (c - b) = 0$ where a, b, c are distinct real numbers such that the matrix $\left[ {\matrix{
{{\alpha ^2}} & \alpha & 1 \cr
1 & 1 & 1 \cr
a & b & c \cr
} } \right]$ is singular. Then, the value of ${{{{(a - c)}^2}} \over {(b - a)(c - b)}} + {{{{(b - a)}^2}} \over {(a - c)(c - b)}} + {{{{(c - b)}^2}} \over {(a - c)(b - a)}}$ is
JEE Mains
2022
MCQ
Which of the following matrices can NOT be obtained from the matrix $\left[\begin{array}{cc}-1 & 2 \\ 1 & -1\end{array}\right]$ by a single elementary row operation ?
JEE Mains
2022
MCQ
If the system of equations
$
\begin{aligned}
&x+y+z=6 \\
&2 x+5 y+\alpha z=\beta \\
&x+2 y+3 z=14
\end{aligned}
$
has infinitely many solutions, then $\alpha+\beta$ is equal to
JEE Mains
2022
MCQ
Let A and B be two $3 \times 3$ non-zero real matrices such that AB is a zero matrix. Then
JEE Mains
2022
MCQ
Let $\mathrm{A}$ and $\mathrm{B}$ be any two $3 \times 3$ symmetric and skew symmetric matrices respectively. Then which of the following is NOT true?
JEE Mains
2022
MCQ
Let the matrix $A=\left[\begin{array}{lll}0 & 1 & 0 \\ 0 & 0 & 1 \\ 1 & 0 & 0\end{array}\right]$ and the matrix $B_{0}=A^{49}+2 A^{98}$. If $B_{n}=A d j\left(B_{n-1}\right)$ for all $n \geq 1$, then $\operatorname{det}\left(B_{4}\right)$ is equal to :
JEE Mains
2022
MCQ
Let $A=\left(\begin{array}{rr}4 & -2 \\ \alpha & \beta\end{array}\right)$.
If $\mathrm{A}^{2}+\gamma \mathrm{A}+18 \mathrm{I}=\mathrm{O}$, then $\operatorname{det}(\mathrm{A})$ is equal to _____________.
JEE Mains
2022
MCQ
Let $A=\left(\begin{array}{cc}1 & 2 \\ -2 & -5\end{array}\right)$. Let $\alpha, \beta \in \mathbb{R}$ be such that $\alpha A^{2}+\beta A=2 I$. Then $\alpha+\beta$ is equal to
JEE Mains
2022
MCQ
$
\text { Let } A=\left[\begin{array}{l}
1 \\
1 \\
1
\end{array}\right] \text { and } B=\left[\begin{array}{ccc}
9^{2} & -10^{2} & 11^{2} \\
12^{2} & 13^{2} & -14^{2} \\
-15^{2} & 16^{2} & 17^{2}
\end{array}\right] \text {, then the value of } A^{\prime} B A \text { is: }
$
JEE Mains
2022
MCQ
If the system of linear equations.
$8x + y + 4z = - 2$
$x + y + z = 0$
$\lambda x - 3y = \mu $
has infinitely many solutions, then the distance of the point $\left( {\lambda ,\mu , - {1 \over 2}} \right)$ from the plane $8x + y + 4z + 2 = 0$ is :
JEE Mains
2022
MCQ
Let A be a 2 $\times$ 2 matrix with det (A) = $-$ 1 and det ((A + I) (Adj (A) + I)) = 4. Then the sum of the diagonal elements of A can be :
JEE Mains
2022
MCQ
The number of real values of $\lambda$, such that the system of linear equations
2x $-$ 3y + 5z = 9
x + 3y $-$ z = $-$18
3x $-$ y + ($\lambda$2 $-$ | $\lambda$ |)z = 16
has no solutions, is
JEE Mains
2022
MCQ
The number of $\theta \in(0,4 \pi)$ for which the system of linear equations
$
\begin{aligned}
&3(\sin 3 \theta) x-y+z=2 \\\\
&3(\cos 2 \theta) x+4 y+3 z=3 \\\\
&6 x+7 y+7 z=9
\end{aligned}
$
has no solution, is :
JEE Mains
2022
MCQ
Let $A = \left[ {\matrix{
1 & { - 2} & \alpha \cr
\alpha & 2 & { - 1} \cr
} } \right]$ and $B = \left[ {\matrix{
2 & \alpha \cr
{ - 1} & 2 \cr
4 & { - 5} \cr
} } \right],\,\alpha \in C$. Then the absolute value of the sum of all values of $\alpha$ for which det(AB) = 0 is :
JEE Mains
2022
MCQ
Let A and B be two square matrices of order 2. If $det\,(A) = 2$, $det\,(B) = 3$ and $\det \left( {(\det \,5(det\,A)B){A^2}} \right) = {2^a}{3^b}{5^c}$ for some a, b, c, $\in$ N, then a + b + c is equal to :
JEE Mains
2022
MCQ
Let $A = \left( {\matrix{
2 & { - 1} \cr
0 & 2 \cr
} } \right)$. If $B = I - {}^5{C_1}(adj\,A) + {}^5{C_2}{(adj\,A)^2} - \,\,.....\,\, - {}^5{C_5}{(adj\,A)^5}$, then the sum of all elements of the matrix B is
JEE Mains
2022
MCQ
If the system of linear equations
2x + y $-$ z = 7
x $-$ 3y + 2z = 1
x + 4y + $\delta$z = k, where $\delta$, k $\in$ R has infinitely many solutions, then $\delta$ + k is equal to:
JEE Mains
2022
MCQ
Let $A = [{a_{ij}}]$ be a square matrix of order 3 such that ${a_{ij}} = {2^{j - i}}$, for all i, j = 1, 2, 3. Then, the matrix A2 + A3 + ...... + A10 is equal to :
JEE Mains
2022
MCQ
If the system of linear equations
$2x + 3y - z = - 2$
$x + y + z = 4$
$x - y + |\lambda |z = 4\lambda - 4$
where, $\lambda$ $\in$ R, has no solution, then
JEE Mains
2022
MCQ
Let A be a matrix of order 3 $\times$ 3 and det (A) = 2. Then det (det (A) adj (5 adj (A3))) is equal to _____________.
JEE Mains
2022
MCQ
Let $f(x) = \left| {\matrix{
a & { - 1} & 0 \cr
{ax} & a & { - 1} \cr
{a{x^2}} & {ax} & a \cr
} } \right|,\,a \in R$. Then the sum of the squares of all the values of a, for which $2f'(10) - f'(5) + 100 = 0$, is
JEE Mains
2022
MCQ
Let A and B be two 3 $\times$ 3 matrices such that $AB = I$ and $|A| = {1 \over 8}$. Then $|adj\,(B\,adj(2A))|$ is equal to
JEE Mains
2022
MCQ
Let the system of linear equations
$x + 2y + z = 2$,
$\alpha x + 3y - z = \alpha $,
$ - \alpha x + y + 2z = - \alpha $
be inconsistent. Then $\alpha$ is equal to :
JEE Mains
2022
MCQ
If the system of equations
$\alpha$x + y + z = 5, x + 2y + 3z = 4, x + 3y + 5z = $\beta$
has infinitely many solutions, then the ordered pair ($\alpha$, $\beta$) is equal to :
JEE Mains
2022
MCQ
Let A be a 3 $\times$ 3 invertible matrix. If |adj (24A)| = |adj (3 adj (2A))|, then |A|2 is equal to :
JEE Mains
2022
MCQ
The ordered pair (a, b), for which the system of linear equations
3x $-$ 2y + z = b
5x $-$ 8y + 9z = 3
2x + y + az = $-$1
has no solution, is :
JEE Mains
2022
MCQ
The system of equations
$ - kx + 3y - 14z = 25$
$ - 15x + 4y - kz = 3$
$ - 4x + y + 3z = 4$
is consistent for all k in the set
JEE Mains
2022
MCQ
Let A be a 3 $\times$ 3 real matrix such that
$A\left( {\matrix{
1 \cr
1 \cr
0 \cr
} } \right) = \left( {\matrix{
1 \cr
1 \cr
0 \cr
} } \right);A\left( {\matrix{
1 \cr
0 \cr
1 \cr
} } \right) = \left( {\matrix{
{ - 1} \cr
0 \cr
1 \cr
} } \right)$ and $A\left( {\matrix{
0 \cr
0 \cr
1 \cr
} } \right) = \left( {\matrix{
1 \cr
1 \cr
2 \cr
} } \right)$.
If $X = {({x_1},{x_2},{x_3})^T}$ and I is an identity matrix of order 3, then the system $(A - 2I)X = \left( {\matrix{
4 \cr
1 \cr
1 \cr
} } \right)$ has :
JEE Mains
2022
MCQ
Let $A = \left[ {\matrix{
0 & { - 2} \cr
2 & 0 \cr
} } \right]$. If M and N are two matrices given by $M = \sum\limits_{k = 1}^{10} {{A^{2k}}} $ and $N = \sum\limits_{k = 1}^{10} {{A^{2k - 1}}} $ then MN2 is :
JEE Mains
2022
MCQ
Let the system of linear equations
x + y + $\alpha$z = 2
3x + y + z = 4
x + 2z = 1
have a unique solution (x$^ * $, y$^ * $, z$^ * $). If ($\alpha$, x$^ * $), (y$^ * $, $\alpha$) and (x$^ * $, $-$y$^ * $) are collinear points, then the sum of absolute values of all possible values of $\alpha$ is
JEE Mains
2022
MCQ
The number of values of $\alpha$ for which the system of equations :
x + y + z = $\alpha$
$\alpha$x + 2$\alpha$y + 3z = $-$1
x + 3$\alpha$y + 5z = 4
is inconsistent, is
JEE Mains
2022
MCQ
Let S = {$\sqrt{n}$ : 1 $\le$ n $\le$ 50 and n is odd}.
Let a $\in$ S and $A = \left[ {\matrix{
1 & 0 & a \cr
{ - 1} & 1 & 0 \cr
{ - a} & 0 & 1 \cr
} } \right]$.
If $\sum\limits_{a\, \in \,S}^{} {\det (adj\,A) = 100\lambda } $, then $\lambda$ is equal to :
JEE Mains
2021
MCQ
Consider the system of linear equations
$-$x + y + 2z = 0
3x $-$ ay + 5z = 1
2x $-$ 2y $-$ az = 7
Let S1 be the set of all a$\in$R for which the system is inconsistent and S2 be the set of all a$\in$R for which the system has infinitely many solutions. If n(S1) and n(S2) denote the number of elements in S1 and S2 respectively, then
JEE Mains
2021
MCQ
If $\alpha$ + $\beta$ + $\gamma$ = 2$\pi$, then the system of equations
x + (cos $\gamma$)y + (cos $\beta$)z = 0
(cos $\gamma$)x + y + (cos $\alpha$)z = 0
(cos $\beta$)x + (cos $\alpha$)y + z = 0
has :
JEE Mains
2021
MCQ
If the following system of linear equations
2x + y + z = 5
x $-$ y + z = 3
x + y + az = b
has no solution, then :
JEE Mains
2021
MCQ
If ${a_r} = \cos {{2r\pi } \over 9} + i\sin {{2r\pi } \over 9}$, r = 1, 2, 3, ....., i = $\sqrt { - 1} $, then
the determinant $\left| {\matrix{
{{a_1}} & {{a_2}} & {{a_3}} \cr
{{a_4}} & {{a_5}} & {{a_6}} \cr
{{a_7}} & {{a_8}} & {{a_9}} \cr
} } \right|$ is equal to :
JEE Mains
2021
MCQ
Let $A = \left( {\matrix{
{[x + 1]} & {[x + 2]} & {[x + 3]} \cr
{[x]} & {[x + 3]} & {[x + 3]} \cr
{[x]} & {[x + 2]} & {[x + 4]} \cr
} } \right)$, where [t] denotes the greatest integer less than or equal to t. If det(A) = 192, then the set of values of x is the interval :
JEE Mains
2021
MCQ
Let A(a, 0), B(b, 2b + 1) and C(0, b), b $\ne$ 0, |b| $\ne$ 1, be points such that the area of triangle ABC is 1 sq. unit, then the sum of all possible values of a is :
JEE Mains
2021
MCQ
Let [$\lambda$] be the greatest integer less than or equal to $\lambda$. The set of all values of $\lambda$ for which the system of linear equations
x + y + z = 4,
3x + 2y + 5z = 3,
9x + 4y + (28 + [$\lambda$])z = [$\lambda$] has a solution is :
JEE Mains
2021
MCQ
If the matrix $A = \left( {\matrix{
0 & 2 \cr
K & { - 1} \cr
} } \right)$ satisfies $A({A^3} + 3I) = 2I$, then the value of K is :
JEE Mains
2021
MCQ
Let $A = \left( {\matrix{
1 & 0 & 0 \cr
0 & 1 & 1 \cr
1 & 0 & 0 \cr
} } \right)$. Then A2025 $-$ A2020 is equal to :
JEE Mains
2021
MCQ
Let $\theta \in \left( {0,{\pi \over 2}} \right)$. If the system of linear equations
$(1 + {\cos ^2}\theta )x + {\sin ^2}\theta y + 4\sin 3\,\theta z = 0$
${\cos ^2}\theta x + (1 + {\sin ^2}\theta )y + 4\sin 3\,\theta z = 0$
${\cos ^2}\theta x + {\sin ^2}\theta y + (1 + 4\sin 3\,\theta )z = 0$
has a non-trivial solution, then the value of $\theta$ is :
JEE Mains
2021
MCQ
If $A = \left( {\matrix{
{{1 \over {\sqrt 5 }}} & {{2 \over {\sqrt 5 }}} \cr
{{{ - 2} \over {\sqrt 5 }}} & {{1 \over {\sqrt 5 }}} \cr
} } \right)$, $B = \left( {\matrix{
1 & 0 \cr
i & 1 \cr
} } \right)$, $i = \sqrt { - 1} $, and Q = ATBA, then the inverse of the matrix A Q2021 AT is equal to :
JEE Mains
2021
MCQ
Let A and B be two 3 $\times$ 3 real matrices such that (A2 $-$ B2) is invertible matrix. If A5 = B5 and A3B2 = A2B3, then the value of the determinant of the matrix A3 + B3 is equal to :
JEE Mains
2021
MCQ
Let $A = \left[ {\matrix{
1 & 2 \cr
{ - 1} & 4 \cr
} } \right]$. If A$-$1 = $\alpha$I + $\beta$A, $\alpha$, $\beta$ $\in$ R, I is a 2 $\times$ 2 identity matrix then 4($\alpha$ $-$ $\beta$) is equal to :
JEE Mains
2021
MCQ
The number of distinct real roots
of $\left| {\matrix{
{\sin x} & {\cos x} & {\cos x} \cr
{\cos x} & {\sin x} & {\cos x} \cr
{\cos x} & {\cos x} & {\sin x} \cr
} } \right| = 0$ in the interval $ - {\pi \over 4} \le x \le {\pi \over 4}$ is :
JEE Mains
2021
MCQ
If $P = \left[ {\matrix{
1 & 0 \cr
{{1 \over 2}} & 1 \cr
} } \right]$, then P50 is :
JEE Mains
2021
MCQ
The values of a and b, for which the system of equations
2x + 3y + 6z = 8
x + 2y + az = 5
3x + 5y + 9z = b
has no solution, are :
JEE Mains
2021
MCQ
The values of $\lambda$ and $\mu$ such that the system of equations $x + y + z = 6$, $3x + 5y + 5z = 26$, $x + 2y + \lambda z = \mu $ has no solution, are :
JEE Mains
2021
MCQ
Let A = [aij] be a real matrix of order 3 $\times$ 3, such that ai1 + ai2 + ai3 = 1, for i = 1, 2, 3. Then, the sum of all the entries of the matrix A3 is equal to :
JEE Mains
2021
MCQ
The value of k $\in$R, for which the following system of linear equations
3x $-$ y + 4z = 3,
x + 2y $-$ 3z = $-$2
6x + 5y + kz = $-$3,
has infinitely many solutions, is :
JEE Mains
2021
MCQ
Let $A = \left[ {\matrix{
2 & 3 \cr
a & 0 \cr
} } \right]$, a$\in$R be written as P + Q where P is a symmetric matrix and Q is skew symmetric matrix. If det(Q) = 9, then the modulus of the sum of all possible values of determinant of P is equal to :
JEE Mains
2021
MCQ
Let the system of linear equations
4x + $\lambda$y + 2z = 0
2x $-$ y + z = 0
$\mu$x + 2y + 3z = 0, $\lambda$, $\mu$$\in$R.
has a non-trivial solution. Then which of the following is true?
JEE Mains
2021
MCQ
The solutions of the equation $\left| {\matrix{
{1 + {{\sin }^2}x} & {{{\sin }^2}x} & {{{\sin }^2}x} \cr
{{{\cos }^2}x} & {1 + {{\cos }^2}x} & {{{\cos }^2}x} \cr
{4\sin 2x} & {4\sin 2x} & {1 + 4\sin 2x} \cr
} } \right| = 0,(0 < x < \pi )$, are
JEE Mains
2021
MCQ
Let $\alpha$, $\beta$, $\gamma$ be the real roots of the equation, x3 + ax2 + bx + c = 0, (a, b, c $\in$ R and a, b $\ne$ 0). If the system of equations (in u, v, w) given by $\alpha$u + $\beta$v + $\gamma$w = 0, $\beta$u + $\gamma$v + $\alpha$w = 0; $\gamma$u + $\alpha$v + $\beta$w = 0 has non-trivial solution, then the value of ${{{a^2}} \over b}$ is
JEE Mains
2021
MCQ
Let $A + 2B = \left[ {\matrix{
1 & 2 & 0 \cr
6 & { - 3} & 3 \cr
{ - 5} & 3 & 1 \cr
} } \right]$ and $2A - B = \left[ {\matrix{
2 & { - 1} & 5 \cr
2 & { - 1} & 6 \cr
0 & 1 & 2 \cr
} } \right]$. If Tr(A) denotes the sum of all diagonal elements of the matrix A, then Tr(A) $-$ Tr(B) has value equal to
JEE Mains
2021
MCQ
If x, y, z are in arithmetic progression with common difference d, x $\ne$ 3d, and the determinant of the matrix $\left[ {\matrix{
3 & {4\sqrt 2 } & x \cr
4 & {5\sqrt 2 } & y \cr
5 & k & z \cr
} } \right]$ is zero, then the value of k2 is :
JEE Mains
2021
MCQ
The system of equations kx + y + z = 1, x + ky + z = k and x + y + zk = k2 has no solution if k is equal to :
JEE Mains
2021
MCQ
If $A = \left( {\matrix{
0 & {\sin \alpha } \cr
{\sin \alpha } & 0 \cr
} } \right)$ and $\det \left( {{A^2} - {1 \over 2}I} \right) = 0$, then a possible value of $\alpha$ is :
JEE Mains
2021
MCQ
Let $A = \left[ {\matrix{
i & { - i} \cr
{ - i} & i \cr
} } \right],i = \sqrt { - 1} $. Then, the system of linear equations ${A^8}\left[ {\matrix{
x \cr
y \cr
} } \right] = \left[ {\matrix{
8 \cr
{64} \cr
} } \right]$ has :
JEE Mains
2021
MCQ
Consider the following system of equations :
x + 2y $-$ 3z = a
2x + 6y $-$ 11z = b
x $-$ 2y + 7z = c,
where a, b and c are real constants. Then the system of equations :
JEE Mains
2021
MCQ
Let A be a symmetric matrix of order 2 with integer entries. If the sum of the diagonal elements of A2 is 1, then the possible number of such matrices is :
JEE Mains
2021
MCQ
The value of $\left| {\matrix{
{(a + 1)(a + 2)} & {a + 2} & 1 \cr
{(a + 2)(a + 3)} & {a + 3} & 1 \cr
{(a + 3)(a + 4)} & {a + 4} & 1 \cr
} } \right|$ is :
JEE Mains
2021
MCQ
Let A be a 3 $\times$ 3 matrix with det(A) = 4. Let Ri denote the ith row of A. If a matrix B is obtained by performing the operation R2 $ \to $ 2R2 + 5R3 on 2A, then det(B) is equal to :
JEE Mains
2021
MCQ
If for the matrix, $A = \left[ {\matrix{
1 & { - \alpha } \cr
\alpha & \beta \cr
} } \right]$, $A{A^T} = {I_2}$, then the value of ${\alpha ^4} + {\beta ^4}$ is :
JEE Mains
2021
MCQ
The following system of linear equations
2x + 3y + 2z = 9
3x + 2y + 2z = 9
x $-$ y + 4z = 8
JEE Mains
2021
MCQ
Let A and B be 3 $\times$ 3 real matrices such that A is symmetric matrix and B is skew-symmetric matrix. Then the system of linear equations (A2B2 $-$ B2A2) X = O, where X is a 3 $\times$ 1 column matrix of unknown variables and O is a 3 $\times$ 1 null matrix, has :
JEE Mains
2021
MCQ
For the system of linear equations:
$x - 2y = 1,x - y + kz = - 2,ky + 4z = 6,k \in R$,
consider the following statements :
(A) The system has unique solution if $k \ne 2,k \ne - 2$.
(B) The system has unique solution if k = $-$2
(C) The system has unique solution if k = 2
(D) The system has no solution if k = 2
(E) The system has infinite number of solutions if k $ \ne $ $-$2.
Which of the following statements are correct?
JEE Mains
2021
MCQ
The system of linear equations
3x - 2y - kz = 10
2x - 4y - 2z = 6
x+2y - z = 5m
is inconsistent if :
JEE Mains
2020
MCQ
Let $\theta = {\pi \over 5}$ and $A = \left[ {\matrix{
{\cos \theta } & {\sin \theta } \cr
{ - \sin \theta } & {\cos \theta } \cr
} } \right]$.
If B = A + A4
, then det (B) :
JEE Mains
2020
MCQ
The values of $\lambda $ and $\mu $ for which the system of linear equations
x + y + z = 2
x + 2y + 3z = 5
x + 3y + $\lambda $z = $\mu $
has infinitely many solutions are, respectively:
JEE Mains
2020
MCQ
Let m and M be respectively the minimum and maximum values of
$\left| {\matrix{
{{{\cos }^2}x} & {1 + {{\sin }^2}x} & {\sin 2x} \cr
{1 + {{\cos }^2}x} & {{{\sin }^2}x} & {\sin 2x} \cr
{{{\cos }^2}x} & {{{\sin }^2}x} & {1 + \sin 2x} \cr
} } \right|$
Then the ordered pair (m, M) is equal to :
JEE Mains
2020
MCQ
If the system of linear equations
x + y + 3z = 0
x + 3y + k2z = 0
3x + y + 3z = 0
has a non-zero solution (x, y, z) for some k $ \in $ R,
then x + $\left( {{y \over z}} \right)$ is equal to :
JEE Mains
2020
MCQ
If a + x = b + y = c + z + 1, where a, b, c, x, y, z
are non-zero distinct real numbers, then
$\left| {\matrix{
x & {a + y} & {x + a} \cr
y & {b + y} & {y + b} \cr
z & {c + y} & {z + c} \cr
} } \right|$ is equal to :
JEE Mains
2020
MCQ
Let $\lambda \in $ R . The system of linear equations
2x1
- 4x2 + $\lambda $x3 = 1
x1 - 6x2 + x3 = 2
$\lambda $x1 - 10x2 + 4x3 = 3
is inconsistent for:
JEE Mains
2020
MCQ
If the minimum and the maximum values of the function $f:\left[ {{\pi \over 4},{\pi \over 2}} \right] \to R$, defined by
$f\left( \theta \right) = \left| {\matrix{
{ - {{\sin }^2}\theta } & { - 1 - {{\sin }^2}\theta } & 1 \cr
{ - {{\cos }^2}\theta } & { - 1 - {{\cos }^2}\theta } & 1 \cr
{12} & {10} & { - 2} \cr
} } \right|$ are m and M respectively, then the ordered pair (m,M) is
equal to :
JEE Mains
2020
MCQ
Suppose the vectors x1, x2 and x3 are the
solutions of the system of linear equations,
Ax = b when the vector b on the right side is equal to b1, b2 and b3 respectively. if
${x_1} = \left[ {\matrix{
1 \cr
1 \cr
1 \cr
} } \right]$, ${x_2} = \left[ {\matrix{
0 \cr
2 \cr
1 \cr
} } \right]$, ${x_3} = \left[ {\matrix{
0 \cr
0 \cr
1 \cr
} } \right]$
${b_1} = \left[ {\matrix{
1 \cr
0 \cr
0 \cr
} } \right]$, ${b_2} = \left[ {\matrix{
0 \cr
2 \cr
0 \cr
} } \right]$ and ${b_3} = \left[ {\matrix{
0 \cr
0 \cr
2 \cr
} } \right]$,
then the determinant of A is equal to :
JEE Mains
2020
MCQ
If the system of equations
x+y+z=2
2x+4y–z=6
3x+2y+$\lambda $z=$\mu $
has infinitely many solutions, then
JEE Mains
2020
MCQ
If $A = \left[ {\matrix{
{\cos \theta } & {i\sin \theta } \cr
{i\sin \theta } & {\cos \theta } \cr
} } \right]$, $\left( {\theta = {\pi \over {24}}} \right)$
and ${A^5} = \left[ {\matrix{
a & b \cr
c & d \cr
} } \right]$, where $i = \sqrt { - 1} $ then which one of the following is
not true?
JEE Mains
2020
MCQ
Let A be a 3 $ \times $ 3 matrix such that
adj A = $\left[ {\matrix{
2 & { - 1} & 1 \cr
{ - 1} & 0 & 2 \cr
1 & { - 2} & { - 1} \cr
} } \right]$ and B = adj(adj A).
If |A| = $\lambda $ and |(B-1)T| = $\mu $ , then the ordered pair,
(|$\lambda $|, $\mu $) is equal to :
JEE Mains
2020
MCQ
If $\Delta $ = $\left| {\matrix{
{x - 2} & {2x - 3} & {3x - 4} \cr
{2x - 3} & {3x - 4} & {4x - 5} \cr
{3x - 5} & {5x - 8} & {10x - 17} \cr
} } \right|$ =
Ax3 + Bx2 + Cx + D, then B + C is equal to :
JEE Mains
2020
MCQ
Let a, b, c $ \in $ R be all non-zero and satisfy
a3 + b3 + c3 = 2. If the matrix
A = $\left( {\matrix{
a & b & c \cr
b & c & a \cr
c & a & b \cr
} } \right)$
satisfies ATA = I, then a value of abc can be :
JEE Mains
2020
MCQ
Let A = {X = (x, y, z)T: PX = 0 and
x2 + y2 + z2 = 1} where
$P = \left[ {\matrix{
1 & 2 & 1 \cr
{ - 2} & 3 & { - 4} \cr
1 & 9 & { - 1} \cr
} } \right]$,
then the set A :
JEE Mains
2020
MCQ
Let S be the set of all $\lambda $ $ \in $ R for which the system
of linear equations
2x – y + 2z = 2
x – 2y +
$\lambda $z = –4
x +
$\lambda $y + z = 4
has no solution. Then the set S :
JEE Mains
2020
MCQ
Let A be a 2 $ \times $ 2 real matrix with entries from
{0, 1} and |A|
$ \ne $ 0. Consider the following two
statements :
(P) If A $ \ne $ I2
, then |A| = –1
(Q) If |A| = 1, then tr(A) = 2,
where I2
denotes 2 $ \times $ 2 identity matrix and tr(A)
denotes the sum of the diagonal entries of A. Then :
JEE Mains
2020
MCQ
The following system of linear equations
7x + 6y – 2z = 0
3x + 4y + 2z = 0
x – 2y – 6z = 0, has
JEE Mains
2020
MCQ
If the matrices A = $\left[ {\matrix{
1 & 1 & 2 \cr
1 & 3 & 4 \cr
1 & { - 1} & 3 \cr
} } \right]$,
B = adjA and
C = 3A, then ${{\left| {adjB} \right|} \over {\left| C \right|}}$ is equal to :
JEE Mains
2020
MCQ
If for some $\alpha $ and $\beta $ in R, the intersection of the
following three places
x + 4y – 2z = 1
x + 7y – 5z = b
x + 5y + $\alpha $z = 5
is a line in R3, then $\alpha $ + $\beta $ is equal to :
JEE Mains
2020
MCQ
If $A = \left( {\matrix{
2 & 2 \cr
9 & 4 \cr
} } \right)$ and $I = \left( {\matrix{
1 & 0 \cr
0 & 1 \cr
} } \right)$ then 10A–1 is
equal to :
JEE Mains
2020
MCQ
The system of linear equations
$\lambda $x + 2y + 2z = 5
2$\lambda $x + 3y + 5z = 8
4x + $\lambda $y + 6z = 10 has
JEE Mains
2020
MCQ
For which of the following ordered pairs ($\mu $, $\delta $),
the system of linear equations
x + 2y + 3z = 1
3x + 4y + 5z = $\mu $
4x + 4y + 4z = $\delta $
is inconsistent ?
JEE Mains
2020
MCQ
Let A = [aij] and B = [bij] be two 3 × 3 real matrices such that bij = (3)(i+j-2)aji, where i, j = 1, 2, 3.
If the determinant of B is 81, then the determinant of A is:
JEE Mains
2020
MCQ
Let $\alpha $ be a root of the equation x2 + x + 1 = 0 and the
matrix A = ${1 \over {\sqrt 3 }}\left[ {\matrix{
1 & 1 & 1 \cr
1 & \alpha & {{\alpha ^2}} \cr
1 & {{\alpha ^2}} & {{\alpha ^4}} \cr
} } \right]$
then the matrix
A31 is equal to
JEE Mains
2020
MCQ
If the system of linear equations
2x + 2ay + az = 0
2x + 3by + bz = 0
2x + 4cy + cz = 0,
where a, b, c $ \in $ R are non-zero distinct; has a non-zero solution, then:
JEE Mains
2019
MCQ
A value of $\theta \in \left( {0,{\pi \over 3}} \right)$, for which
$\left| {\matrix{
{1 + {{\cos }^2}\theta } & {{{\sin }^2}\theta } & {4\cos 6\theta } \cr
{{{\cos }^2}\theta } & {1 + {{\sin }^2}\theta } & {4\cos 6\theta } \cr
{{{\cos }^2}\theta } & {{{\sin }^2}\theta } & {1 + 4\cos 6\theta } \cr
} } \right| = 0$, is :
JEE Mains
2019
MCQ
If $B = \left[ {\matrix{
5 & {2\alpha } & 1 \cr
0 & 2 & 1 \cr
\alpha & 3 & { - 1} \cr
} } \right]$ is the inverse of a 3 × 3 matrix A, then the sum of all values of $\alpha $ for which
det(A) + 1 = 0, is :
JEE Mains
2019
MCQ
If A is a symmetric matrix and B is a skew-symmetric matrix such that A + B = $\left[ {\matrix{
2 & 3 \cr
5 & { - 1} \cr
} } \right]$, then AB is equal
to :
JEE Mains
2019
MCQ
Let $\lambda $ be a real number for which the system of linear equations x + y + z = 6, 4x + $\lambda $y – $\lambda $z = $\lambda $ – 2,
3x + 2y – 4z = – 5 has infinitely many solutions. Then $\lambda $ is a root of the quadratic equation:
JEE Mains
2019
MCQ
The sum of the real roots of the equation
$\left| {\matrix{
x & { - 6} & { - 1} \cr
2 & { - 3x} & {x - 3} \cr
{ - 3} & {2x} & {x + 2} \cr
} } \right| = 0$, is equal to :
JEE Mains
2019
MCQ
If the system of linear equations
x + y + z = 5
x + 2y + 2z = 6
x + 3y + $\lambda $z = $\mu $, ($\lambda $, $\mu $ $ \in $ R), has infinitely many solutions, then the value of $\lambda $ + $\mu $ is :
JEE Mains
2019
MCQ
If ${\Delta _1} = \left| {\matrix{
x & {\sin \theta } & {\cos \theta } \cr
{ - \sin \theta } & { - x} & 1 \cr
{\cos \theta } & 1 & x \cr
} } \right|$ and
${\Delta _2} = \left| {\matrix{
x & {\sin 2\theta } & {\cos 2\theta } \cr
{ - \sin 2\theta } & { - x} & 1 \cr
{\cos 2\theta } & 1 & x \cr
} } \right|$, $x \ne 0$ ;
then for all $\theta \in \left( {0,{\pi \over 2}} \right)$ :
JEE Mains
2019
MCQ
If the system of equations 2x + 3y – z = 0, x + ky
– 2z = 0 and 2x – y + z = 0 has a non-trival solution
(x, y, z), then ${x \over y} + {y \over z} + {z \over x} + k$
is equal to :-
JEE Mains
2019
MCQ
The total number of matrices
$A = \left( {\matrix{
0 & {2y} & 1 \cr
{2x} & y & { - 1} \cr
{2x} & { - y} & 1 \cr
} } \right)$
(x, y $ \in $ R,x $ \ne $ y) for which ATA = 3I3 is :-
JEE Mains
2019
MCQ
If $\left[ {\matrix{
1 & 1 \cr
0 & 1 \cr
} } \right]\left[ {\matrix{
1 & 2 \cr
0 & 1 \cr
} } \right]$$\left[ {\matrix{
1 & 3 \cr
0 & 1 \cr
} } \right]$....$\left[ {\matrix{
1 & {n - 1} \cr
0 & 1 \cr
} } \right] = \left[ {\matrix{
1 & {78} \cr
0 & 1 \cr
} } \right]$,
then the inverse of $\left[ {\matrix{
1 & n \cr
0 & 1 \cr
} } \right]$ is
JEE Mains
2019
MCQ
Let $\alpha $ and $\beta $ be the roots of the equation
x2 + x + 1 = 0. Then for y $ \ne $ 0 in R,
$$\left| {\matrix{
{y + 1} & \alpha & \beta \cr
\alpha & {y + \beta } & 1 \cr
\beta & 1 & {y + \alpha } \cr
} } \right|$$
is equal to
JEE Mains
2019
MCQ
Let the number 2,b,c be in an A.P. and
A = $\left[ {\matrix{
1 & 1 & 1 \cr
2 & b & c \cr
4 & {{b^2}} & {{c^2}} \cr
} } \right]$. If det(A) $ \in $ [2, 16], then c
lies in the interval :
JEE Mains
2019
MCQ
The greatest value of c $ \in $ R for which the system
of linear equations
x – cy – cz = 0
cx – y + cz = 0
cx + cy – z = 0
has a non-trivial solution, is :
JEE Mains
2019
MCQ
Let $A = \left( {\matrix{
{\cos \alpha } & { - \sin \alpha } \cr
{\sin \alpha } & {\cos \alpha } \cr
} } \right)$, ($\alpha $ $ \in $ R)
such that ${A^{32}} = \left( {\matrix{
0 & { - 1} \cr
1 & 0 \cr
} } \right)$ then a value of $\alpha $ is
JEE Mains
2019
MCQ
The set of all values of $\lambda $ for which the system of linear equations
x – 2y – 2z = $\lambda $x
x + 2y + z = $\lambda $y
– x – y = $\lambda $z
has a non-trivial solutions :
JEE Mains
2019
MCQ
If A = $\left[ {\matrix{
1 & {\sin \theta } & 1 \cr
{ - \sin \theta } & 1 & {\sin \theta } \cr
{ - 1} & { - \sin \theta } & 1 \cr
} } \right]$;
then for all $\theta $ $ \in $ $\left( {{{3\pi } \over 4},{{5\pi } \over 4}} \right)$, det (A) lies in the interval :
JEE Mains
2019
MCQ
Let P = $\left[ {\matrix{
1 & 0 & 0 \cr
3 & 1 & 0 \cr
9 & 3 & 1 \cr
} } \right]$ and Q = [qij] be two 3 $ \times $ 3 matrices such that Q – P5 = I3.
Then ${{{q_{21}} + {q_{31}}} \over {{q_{32}}}}$ is equal to :
JEE Mains
2019
MCQ
An ordered pair ($\alpha $, $\beta $) for which the system of linear equations
(1 + $\alpha $) x + $\beta $y + z = 2
$\alpha $x + (1 + $\beta $)y + z = 3
$\alpha $x + $\beta $y + 2z = 2
has a unique solution, is :
JEE Mains
2019
MCQ
If $\left| {\matrix{
{a - b - c} & {2a} & {2a} \cr
{2b} & {b - c - a} & {2b} \cr
{2c} & {2c} & {c - a - b} \cr
} } \right|$
= (a + b + c) (x + a + b + c)2, x $ \ne $ 0,
then x is equal to :
JEE Mains
2019
MCQ
Let A and B be two invertible matrices of order 3 $ \times $ 3. If det(ABAT) = 8 and det(AB–1) = 8,
then det (BA–1 BT) is equal to :
JEE Mains
2019
MCQ
If the system of linear equations
2x + 2y + 3z = a
3x – y + 5z = b
x – 3y + 2z = c
where a, b, c are non zero real numbers, has more one solution, then :
JEE Mains
2019
MCQ
Let A = $\left( {\matrix{
0 & {2q} & r \cr
p & q & { - r} \cr
p & { - q} & r \cr
} } \right).$ If AAT = I3, then $\left| p \right|$ is :
JEE Mains
2019
MCQ
Let A = $\left[ {\matrix{
2 & b & 1 \cr
b & {{b^2} + 1} & b \cr
1 & b & 2 \cr
} } \right]$ where b > 0.
Then the minimum value of ${{\det \left( A \right)} \over b}$ is -
JEE Mains
2019
MCQ
The number of values of $\theta $ $ \in $ (0, $\pi $) for which the system of linear equations
x + 3y + 7z = 0
$-$ x + 4y + 7z = 0
(sin3$\theta $)x + (cos2$\theta $)y + 2z = 0.
has a non-trival solution, is -
JEE Mains
2019
MCQ
If the system of equations
x + y + z = 5
x + 2y + 3z = 9
x + 3y + az = $\beta $
has infinitely many solutions, then $\beta $ $-$ $\alpha $ equals -
JEE Mains
2019
MCQ
Let d $ \in $ R, and
$A = \left[ {\matrix{
{ - 2} & {4 + d} & {\left( {\sin \theta } \right) - 2} \cr
1 & {\left( {\sin \theta } \right) + 2} & d \cr
5 & {\left( {2\sin \theta } \right) - d} & {\left( { - \sin \theta } \right) + 2 + 2d} \cr
} } \right],$
$\theta \in \left[ {0,2\pi } \right]$ If the minimum value of det(A) is 8,
then a value of d is -
JEE Mains
2019
MCQ
If the system of linear equations
x $-$ 4y + 7z = g
3y $-$ 5z = h
$-$2x + 5y $-$ 9z = k
is consistent, then :
JEE Mains
2019
MCQ
If $A = \left[ {\matrix{
{{e^t}} & {{e^{ - t}}\cos t} & {{e^{ - t}}\sin t} \cr
{{e^t}} & { - {e^{ - t}}\cos t - {e^{ - t}}\sin t} & { - {e^{ - t}}\sin t + {e^{ - t}}co{\mathop{\rm s}\nolimits} t} \cr
{{e^t}} & {2{e^{ - t}}\sin t} & { - 2{e^{ - t}}\cos t} \cr
} } \right]$
then A is :
JEE Mains
2019
MCQ
The system of linear equations
x + y + z = 2
2x + 3y + 2z = 5
2x + 3y + (a2 – 1) z = a + 1 then
JEE Mains
2019
MCQ
If $A = \left[ {\matrix{
{\cos \theta } & { - \sin \theta } \cr
{\sin \theta } & {\cos \theta } \cr
} } \right]$, then the matrix A–50 when $\theta $ = $\pi \over 12$, is equal to :
JEE Mains
2018
MCQ
Let A = $\left[ {\matrix{
1 & 0 & 0 \cr
1 & 1 & 0 \cr
1 & 1 & 1 \cr
} } \right]$ and B = A20. Then the sum of the elements of the first column of B is :
JEE Mains
2018
MCQ
The number of values of k for which the system of linear equations,
(k + 2)x + 10y = k
kx + (k +3)y = k -1
has no solution, is :
JEE Mains
2018
MCQ
If $\left| {\matrix{
{x - 4} & {2x} & {2x} \cr
{2x} & {x - 4} & {2x} \cr
{2x} & {2x} & {x - 4} \cr
} } \right| = \left( {A + Bx} \right){\left( {x - A} \right)^2}$
then the ordered pair (A, B) is equal to :
JEE Mains
2018
MCQ
If the system of linear equations
x + ky + 3z = 0
3x + ky - 2z = 0
2x + 4y - 3z = 0
has a non-zero solution (x, y, z), then ${{xz} \over {{y^2}}}$ is equal to
JEE Mains
2018
MCQ
If the system of linear equations
x + ay + z = 3
x + 2y + 2z = 6
x + 5y + 3z = b
has no solution, then :
JEE Mains
2018
MCQ
Suppose A is any 3$ \times $ 3 non-singular matrix and ( A $-$ 3I) (A $-$ 5I) = O where I = I3 and O = O3. If $\alpha $A + $\beta $A-1 = 4I, then $\alpha $ + $\beta $ is equal to :
JEE Mains
2018
MCQ
Let $A$ be a matrix such that $A.\left[ {\matrix{
1 & 2 \cr
0 & 3 \cr
} } \right]$ is a scalar matrix and |3A| = 108.
Then A2 equals :
JEE Mains
2018
MCQ
Let S be the set of all real values of k for which the systemof linear equations
x + y + z = 2
2x + y $-$ z = 3
3x + 2y + kz = 4
has a unique solution. Then S is :
JEE Mains
2017
MCQ
For two 3 × 3 matrices A and B, let A + B = 2BT and 3A + 2B = I3, where BT is
the transpose of B and I3 is 3 × 3 identity matrix. Then :
JEE Mains
2017
MCQ
The number of real values of $\lambda $ for which the system of linear equations
2x + 4y $-$ $\lambda $z = 0
4x + $\lambda $y + 2z = 0
$\lambda $x + 2y + 2z = 0
has infinitely many solutions, is :
JEE Mains
2017
MCQ
Let A be any 3 $ \times $ 3 invertible matrix. Then which one of the following is not always true ?
JEE Mains
2017
MCQ
If
$S = \left\{ {x \in \left[ {0,2\pi } \right]:\left| {\matrix{
0 & {\cos x} & { - \sin x} \cr
{\sin x} & 0 & {\cos x} \cr
{\cos x} & {\sin x} & 0 \cr
} } \right| = 0} \right\},$
then $\sum\limits_{x \in S} {\tan \left( {{\pi \over 3} + x} \right)} $ is equal to :
JEE Mains
2017
MCQ
If S is the set of distinct values of 'b' for which the following system of linear equations
x + y + z = 1
x + ay + z = 1
ax + by + z = 0
has no solution, then S is :
JEE Mains
2017
MCQ
If $A = \left[ {\matrix{
2 & { - 3} \cr
{ - 4} & 1 \cr
} } \right]$,
then adj(3A2 + 12A) is equal to
JEE Mains
2016
MCQ
If A = $\left[ {\matrix{
{ - 4} & { - 1} \cr
3 & 1 \cr
} } \right]$,
then the determinant of the matrix (A2016 − 2A2015 − A2014) is :
JEE Mains
2016
MCQ
Let A be a 3 $ \times $ 3 matrix such that A2 $-$ 5A + 7I = 0
Statement - I :
A$-$1 = ${1 \over 7}$ (5I $-$ A).
Statement - II :
The polynomial A3 $-$ 2A2 $-$ 3A + I can be reduced to 5(A $-$ 4I).
Then :
JEE Mains
2016
MCQ
If P = $\left[ {\matrix{
{{{\sqrt 3 } \over 2}} & {{1 \over 2}} \cr
{ - {1 \over 2}} & {{{\sqrt 3 } \over 2}} \cr
} } \right],A = \left[ {\matrix{
1 & 1 \cr
0 & 1 \cr
} } \right]\,\,\,$
Q = PAPT, then PT Q2015 P is :
JEE Mains
2016
MCQ
The number of distinct real roots of the equation,
$\left| {\matrix{
{\cos x} & {\sin x} & {\sin x} \cr
{\sin x} & {\cos x} & {\sin x} \cr
{\sin x} & {\sin x} & {\cos x} \cr
} } \right| = 0$ in the interval $\left[ { - {\pi \over 4},{\pi \over 4}} \right]$ is :
JEE Mains
2016
MCQ
The system of linear equations
$\matrix{
{x + \lambda y - z = 0} \cr
{\lambda x - y - z = 0} \cr
{x + y - \lambda z = 0} \cr
} $
has a non-trivial solution for :
JEE Mains
2016
MCQ
If $A = \left[ {\matrix{
{5a} & { - b} \cr
3 & 2 \cr
} } \right]$ and $A$ adj $A=A$ ${A^T},$ then $5a+b$ is equal to :
JEE Mains
2015
MCQ
If $A = \left[ {\matrix{
1 & 2 & 2 \cr
2 & 1 & { - 2} \cr
a & 2 & b \cr
} } \right]$ is a matrix satisfying the equation
$A{A^T} = 9\text{I},$ where $I$ is $3 \times 3$ identity matrix, then the ordered
pair $(a, b)$ is equal to :
JEE Mains
2015
MCQ
The set of all values of $\lambda $ for which the system of linear equations:
$\matrix{
{2{x_1} - 2{x_2} + {x_3} = \lambda {x_1}} \cr
{2{x_1} - 3{x_2} + 2{x_3} = \lambda {x_2}} \cr
{ - {x_1} + 2{x_2} = \lambda {x_3}} \cr
} $
has a non-trivial solution
JEE Mains
2014
MCQ
If $A$ is a $3 \times 3$ non-singular matrix such that $AA'=A'A$ and
$B = {A^{ - 1}}A',$ then $BB'$ equals:
JEE Mains
2014
MCQ
If $\alpha ,\beta \ne 0,$ and $f\left( n \right) = {\alpha ^n} + {\beta ^n}$ and
$$\left| {\matrix{
3 & {1 + f\left( 1 \right)} & {1 + f\left( 2 \right)} \cr
{1 + f\left( 1 \right)} & {1 + f\left( 2 \right)} & {1 + f\left( 3 \right)} \cr
{1 + f\left( 2 \right)} & {1 + f\left( 3 \right)} & {1 + f\left( 4 \right)} \cr
} } \right|$$
$ = K{\left( {1 - \alpha } \right)^2}{\left( {1 - \beta } \right)^2}{\left( {\alpha - \beta } \right)^2},$ then $K$ is equal to :
JEE Mains
2013
MCQ
The number of values of $k$, for which the system of equations : $$\matrix{
{\left( {k + 1} \right)x + 8y = 4k} \cr
{kx + \left( {k + 3} \right)y = 3k - 1} \cr
} $$
has no solution, is
JEE Mains
2013
MCQ
If $P = \left[ {\matrix{
1 & \alpha & 3 \cr
1 & 3 & 3 \cr
2 & 4 & 4 \cr
} } \right]$ is the adjoint of a $3 \times 3$ matrix $A$ and
$\left| A \right| = 4,$ then $\alpha $ is equal to :
JEE Mains
2012
MCQ
Let $P$ and $Q$ be $3 \times 3$ matrices $P \ne Q.$ If ${P^3} = {Q^3}$ and
${P^2}Q = {Q^2}P$ then determinant of $\left( {{P^2} + {Q^2}} \right)$ is equal to :
JEE Mains
2012
MCQ
Let $A = \left( {\matrix{
1 & 0 & 0 \cr
2 & 1 & 0 \cr
3 & 2 & 1 \cr
} } \right)$. If ${u_1}$ and ${u_2}$ are column matrices such
that $A{u_1} = \left( {\matrix{
1 \cr
0 \cr
0 \cr
} } \right)$ and $A{u_2} = \left( {\matrix{
0 \cr
1 \cr
0 \cr
} } \right),$ then ${u_1} + {u_2}$ is equal to :
JEE Mains
2011
MCQ
The number of values of $k$ for which the linear equations
$4x + ky + 2z = 0,kx + 4y + z = 0$ and $2x+2y+z=0$ possess a non-zero solution is :
JEE Mains
2011
MCQ
Let $A$ and $B$ be two symmetric matrices of order $3$.
Statement - 1 : $A(BA)$ and $(AB)$$A$ are symmetric matrices.
Statement - 2 : $AB$ is symmetric matrix if matrix multiplication of $A$ with $B$ is commutative.
JEE Mains
2010
MCQ
The number of $3 \times 3$ non-singular matrices, with four entries as $1$ and all other entries as $0$, is :
JEE Mains
2010
MCQ
Let $A$ be a $\,2 \times 2$ matrix with non-zero entries and let ${A^2} = I,$
where $I$ is $2 \times 2$ identity matrix. Define
$Tr$$(A)=$ sum of diagonal elements of $A$ and $\left| A \right| = $ determinant of matrix $A$.
Statement- 1: $Tr$$(A)=0$.
Statement- 2: $\left| A \right| = 1$ .
JEE Mains
2010
MCQ
Consider the system of linear equations;
$$\matrix{
{{x_1} + 2{x_2} + {x_3} = 3} \cr
{2{x_1} + 3{x_2} + {x_3} = 3} \cr
{3{x_1} + 5{x_2} + 2{x_3} = 1} \cr
} $$
The system has :
JEE Mains
2009
MCQ
Let $A$ be a $\,2 \times 2$ matrix
Statement - 1 : $adj\left( {adj\,A} \right) = A$
Statement - 2 :$\left| {adj\,A} \right| = \left| A \right|$
JEE Mains
2009
MCQ
Let $a, b, c$ be such that $b\left( {a + c} \right) \ne 0$ if
$\left| {\matrix{
a & {a + 1} & {a - 1} \cr
{ - b} & {b + 1} & {b - 1} \cr
c & {c - 1} & {c + 1} \cr
} } \right| + \left| {\matrix{
{a + 1} & {b + 1} & {c - 1} \cr
{a - 1} & {b - 1} & {c + 1} \cr
{{{\left( { - 1} \right)}^{n + 2}}a} & {{{\left( { - 1} \right)}^{n + 1}}b} & {{{\left( { - 1} \right)}^n}c} \cr
} } \right| = 0$
then the value of $n$ :
JEE Mains
2008
MCQ
Let $a, b, c$ be any real numbers. Suppose that there are real numbers $x, y, z$ not all zero such that $x=cy+bz,$ $y=az+cx,$ and $z=bx+ay.$ Then ${a^2} + {b^2} + {c^2} + 2abc$ is equal to :
JEE Mains
2008
MCQ
Let $A$ be $a\,2 \times 2$ matrix with real entries. Let $I$ be the $2 \times 2$ identity matrix. Denote by tr$(A)$, the sum of diagonal entries of $a$. Assume that ${a^2} = I.$
Statement-1 : If $A \ne I$ and $A \ne - I$, then det$(A)=-1$
Statement- 2 : If $A \ne I$ and $A \ne - I$, then tr $(A)$ $ \ne 0$.
JEE Mains
2008
MCQ
Let $A$ be a square matrix all of whose entries are integers.
Then which one of the following is true?
JEE Mains
2007
MCQ
Let $A = \left| {\matrix{
5 & {5\alpha } & \alpha \cr
0 & \alpha & {5\alpha } \cr
0 & 0 & 5 \cr
} } \right|.$ If $\,\,\left| {{A^2}} \right| = 25,$ then $\,\left| \alpha \right|$ equals
JEE Mains
2007
MCQ
If $D = \left| {\matrix{
1 & 1 & 1 \cr
1 & {1 + x} & 1 \cr
1 & 1 & {1 + y} \cr
} } \right|$ for $x \ne 0,y \ne 0,$ then $D$ is :
JEE Mains
2006
MCQ
If $A$ and $B$ are square matrices of size $n\, \times \,n$ such that
${A^2} - {B^2} = \left( {A - B} \right)\left( {A + B} \right),$ then which of the following will be always true?
JEE Mains
2006
MCQ
Let $A = \left( {\matrix{
1 & 2 \cr
3 & 4 \cr
} } \right)$ and $B = \left( {\matrix{
a & 0 \cr
0 & b \cr
} } \right),a,b \in N.$ Then
JEE Mains
2005
MCQ
The system of equations
$\matrix{
{\alpha \,x + y + z = \alpha - 1} \cr
{x + \alpha y + z = \alpha - 1} \cr
{x + y + \alpha \,z = \alpha - 1} \cr
} $
has no solutions, if $\alpha $ is :
JEE Mains
2005
MCQ
If ${a_1},{a_2},{a_3},........,{a_n},.....$ are in G.P., then the determinant
$$\Delta = \left| {\matrix{
{\log {a_n}} & {\log {a_{n + 1}}} & {\log {a_{n + 2}}} \cr
{\log {a_{n + 3}}} & {\log {a_{n + 4}}} & {\log {a_{n + 5}}} \cr
{\log {a_{n + 6}}} & {\log {a_{n + 7}}} & {\log {a_{n + 8}}} \cr
} } \right|$$
is equal to :
JEE Mains
2005
MCQ
If ${A^2} - A + 1 = 0$, then the inverse of $A$ is :
JEE Mains
2005
MCQ
If ${a^2} + {b^2} + {c^2} = - 2$ and
f$\left( x \right) = \left| {\matrix{
{1 + {a^2}x} & {\left( {1 + {b^2}} \right)x} & {\left( {1 + {c^2}} \right)x} \cr
{\left( {1 + {a^2}} \right)x} & {1 + {b^2}x} & {\left( {1 + {c^2}} \right)x} \cr
{\left( {1 + {a^2}} \right)x} & {\left( {1 + {b^2}} \right)x} & {1 + {c^2}x} \cr
} } \right|,$
then f$(x)$ is a polynomial of degree :
JEE Mains
2004
MCQ
Let $A = \left( {\matrix{
1 & { - 1} & 1 \cr
2 & 1 & { - 3} \cr
1 & 1 & 1 \cr
} } \right).$ and $10$ $B = \left( {\matrix{
4 & 2 & 2 \cr
{ - 5} & 0 & \alpha \cr
1 & { - 2} & 3 \cr
} } \right)$. if $B$ is
the inverse of matrix $A$, then $\alpha $ is
JEE Mains
2004
MCQ
If ${a_1},{a_2},{a_3},.........,{a_n},......$ are in G.P., then the value of the determinant
$\left| {\matrix{
{\log {a_n}} & {\log {a_{n + 1}}} & {\log {a_{n + 2}}} \cr
{\log {a_{n + 3}}} & {\log {a_{n + 4}}} & {\log {a_{n + 5}}} \cr
{\log {a_{n + 6}}} & {\log {a_{n + 7}}} & {\log {a_{n + 8}}} \cr
} } \right|,$ is
JEE Mains
2004
MCQ
Let $A = \left( {\matrix{
0 & 0 & { - 1} \cr
0 & { - 1} & 0 \cr
{ - 1} & 0 & 0 \cr
} } \right)$. The only correct
statement about the matrix $A$ is
JEE Mains
2003
MCQ
If $1,$ $\omega ,{\omega ^2}$ are the cube roots of unity, then
$\Delta = \left| {\matrix{
1 & {{\omega ^n}} & {{\omega ^{2n}}} \cr
{{\omega ^n}} & {{\omega ^{2n}}} & 1 \cr
{{\omega ^{2n}}} & 1 & {{\omega ^n}} \cr
} } \right|$ is equal to
JEE Mains
2003
MCQ
If the system of linear equations
$x + 2ay + az = 0;$ $x + 3by + bz = 0;\,\,x + 4cy + cz = 0;$
has a non - zero solution, then $a, b, c$.
JEE Mains
2003
MCQ
If $A = \left[ {\matrix{
a & b \cr
b & a \cr
} } \right]$ and ${A^2} = \left[ {\matrix{
\alpha & \beta \cr
\beta & \alpha \cr
} } \right]$, then
JEE Mains
2002
MCQ
If $a>0$ and discriminant of $\,a{x^2} + 2bx + c$ is $-ve$, then
$\left| {\matrix{
a & b & {ax + b} \cr
b & c & {bx + c} \cr
{ax + b} & {bx + c} & 0 \cr
} } \right|$ is equal to