iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Let the tangent to the circle x2 + y2 = 25 at the point R(3, 4) meet x-axis and y-axis at points P and Q, respectively. If r is the radius of the circle passing through the origin O and having centre at the incentre of the triangle OPQ, then r2 is equal to :
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Two tangents are drawn from a point P to the circle x2 + y2 $-$ 2x $-$ 4y + 4 = 0, such that the angle between these tangents is ${\tan ^{ - 1}}\left( {{{12} \over 5}} \right)$, where ${\tan ^{ - 1}}\left( {{{12} \over 5}} \right)$ $\in$(0, $\pi$). If the centre of the circle is denoted by C and these tangents touch the circle at points A and B, then the ratio of the areas of $\Delta$PAB and $\Delta$CAB is :
A.
3 : 1
B.
9 : 4
C.
2 : 1
D.
11 : 4
Correct Answer: B
Explanation:
Let $\theta$ = tan$-$1$\left( {{{12} \over 5}} \right)$
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The line 2x $-$ y + 1 = 0 is a tangent to the circle at the point (2, 5) and the centre of the circle lies on x $-$ 2y = 4. Then, the radius of the circle is :
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Choose the incorrect statement about the two circles whose equations are given below :
x2 + y2 $-$ 10x $-$ 10y + 41 = 0 and
x2 + y2 $-$ 16x $-$ 10y + 80 = 0
A.
Distance between two centres is the average of radii of both the circles.
B.
Both circles pass through the centre of each other.
C.
Circles have two intersection points.
D.
Both circle's centers lie inside region of one another.
Correct Answer: D
Explanation:
S1 $ \equiv $ x2 + y2 $-$ 10x $-$ 10y + 41 = 0
Centre C1 $ \equiv $ (5, 5), radius r1 = 3
S2 $ \equiv $ x2 + y2 $-$ 16x $-$ 10y + 80 = 0
Centre C2 $ \equiv $ (8, 5), radius r2 = 3
Distance between centres = 3
Hence both circles pass through the centre of each other, have two intersection point and distance between two centres in average of radii of both the circles.
Hence, option (d) is the incorrect statement.
2021
Q105
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Let the lengths of intercepts on x-axis and y-axis made by the circle x2 + y2 + ax + 2ay + c = 0, (a < 0) be 2${\sqrt 2 }$ and 2${\sqrt 5 }$, respectively. Then the shortest distance from origin to a tangent to this circle which is perpendicular to the line x + 2y = 0, is equal to :
A.
${\sqrt {10} }$
B.
${\sqrt {6} }$
C.
${\sqrt {11} }$
D.
${\sqrt {7} }$
Correct Answer: B
Explanation:
$2\sqrt {{{{a^2}} \over 4} - c} = 2\sqrt 2 $
$\sqrt {{a^2} - 4c} = 2\sqrt 2 $
${a^2} - 4c = 8$ .... (1)
$2\sqrt {{a^2} - c} = 2\sqrt 5 $
${a^2} - c = 5$ .... (2)
$(2) - (1)$
$3c = - 3a \Rightarrow c = - 1$
${a^2} = 4 \Rightarrow a = - 2$ (Given a < 0)
Equation of circle
${x^2} + {y^2} - 2x - 4y - 1 = 0$
Equation of tangent which is perpendicular to the line x + 2y = 0 is
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Let A(1, 4) and B(1, $-$5) be two points. Let P be a point on the circle (x $-$ 1)2 + (y $-$ 1)2 = 1 such that (PA)2 + (PB)2 have maximum value, then the points, P, A and B lie on :
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If the locus of the mid-point of the line segment from the point (3, 2) to a point on the circle, x2 + y2 = 1 is a circle of radius r, then r is equal to :
A.
${1 \over 4}$
B.
${1 \over 2}$
C.
1
D.
${1 \over 3}$
Correct Answer: B
Explanation:
Let P(h, k) and point on the circle is (cos$\theta$, sin$\theta$)
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Let B be the centre of the circle x2 + y2 $-$ 2x + 4y + 1 = 0. Let the tangents at two points P and Q on the circle intersect at the point A(3, 1). Then 8.$\left( {{{area\,\Delta APQ} \over {area\,\Delta BPQ}}} \right)$ is equal to _____________.
Correct Answer: 18
Explanation:
Radius = $\sqrt {1 + 4 - 1} = 2$
$AB = \sqrt {{3^2} + {2^2}} = \sqrt {13} $
In $\Delta$ABP
$A{P^2} = A{B^2} - B{P^2} = 13 - 4 = 9$
AP = 3
AQ = AP = 3
Let $\angle$ABP = $\theta$, $\angle$BAP = 90$-$ $\theta$
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If the variable line 3x + 4y = $\alpha$ lies between the two circles (x $-$ 1)2 + (y $-$ 1)2 = 1 and (x $-$ 9)2 + (y $-$ 1)2 = 4, without intercepting a chord on either circle, then the sum of all the integral values of $\alpha$ is ___________.
Correct Answer: 165
Explanation:
Both centers should lie on either side of the line as well as line can be tangent to circle.
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Two circles each of radius 5 units touch each other at the point (1, 2). If the equation of their common tangent is 4x + 3y = 10, and C1($\alpha$, $\beta$) and C2($\gamma$, $\delta$), C1 $\ne$ C2 are their centres, then |($\alpha$ + $\beta$) ($\gamma$ + $\delta$)| is equal to ___________.
Correct Answer: 40
Explanation:
Slope of line joining centres of circles = ${4 \over 3} = \tan \theta $
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Let the equation x2 + y2 + px + (1 $-$ p)y + 5 = 0 represent circles of varying radius r $\in$ (0, 5]. Then the number of elements in the set S = {q : q = p2 and q is an integer} is __________.
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The locus of a point, which moves such that the sum of squares of its distances from the points (0, 0), (1, 0), (0, 1), (1, 1) is 18 units, is a circle of diameter d. Then d2 is equal to _____________.
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The minimum distance between any two points P1 and P2 while considering point P1 on one circle and point P2 on the other circle for the given circles' equations
x2 + y2 $-$ 10x $-$ 10y + 41 = 0
x2 + y2 $-$ 24x $-$ 10y + 160 = 0 is ___________.
Correct Answer: 1
Explanation:
${S_1}:{(x - 5)^2} + {(y - 5)^2} = 9$
Centre (5, 5), r1 = 3
${S_2}:{(x - 12)^2} + {(y - 5)^2} = 9$
Centre (12, 5), r2 = 3
So (P1P2)min = 1
2021
Q115
JEE Mains
Numerical
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Let a point P be such that its distance from the point (5, 0) is thrice the distance of P from the point ($-$5, 0). If the locus of the point P is a circle of radius r, then 4r2 is equal to ________
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If the area of the triangle formed by the positive x-axis, the normal and the tangent to the circle (x $-$ 2)2 + (y $-$ 3)2 = 25 at the point (5, 7) is A, then 24A is equal to _________.
Correct Answer: 1225
Explanation:
This question is bonus if we consider poistive x axis.If we consider only x axis for this question then it is right question.
2021
Q117
JEE Mains
Numerical
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If one of the diameters of the circle x2 + y2 - 2x - 6y + 6 = 0 is a chord of another circle 'C',
whose center is at (2, 1), then its radius is ________.
Correct Answer: 3
Explanation:
Circle x2 + y2 - 2x - 6y + 6 = 0 has centre
O1(1, 3) and radius r
= 2.
Let centre O2
(2, 1) of required circle and its
radius being r.
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The circle passing through the intersection of the circles, x2 + y2 – 6x = 0 and x2 + y2 – 4y = 0, having its centre on the line, 2x – 3y + 12 = 0, also passes through the point :
A.
(–3, 1)
B.
(1, –3)
C.
(–1, 3)
D.
(–3, 6)
Correct Answer: D
Explanation:
Let S be the circle passing through point of intersection of S1 & S2
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If a line, y = mx + c is a tangent to the circle,
(x – 3)2 + y2 = 1 and it is perpendicular to a line L1, where L1 is the tangent to the circle, x2 + y2 = 1 at the point $\left( {{1 \over {\sqrt 2 }},{1 \over {\sqrt 2 }}} \right)$, then :
A.
c2 + 6c + 7 = 0
B.
c2 - 7c + 6 = 0
C.
c2 – 6c + 7 = 0
D.
c2 + 7c + 6 = 0
Correct Answer: A
Explanation:
For circle x2 + y2
= 1 tangnet at point P$\left( {{1 \over {\sqrt 2 }},{1 \over {\sqrt 2 }}} \right)$ is
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Let PQ be a diameter of the circle x2 + y2 = 9. If $\alpha $ and $\beta $ are the lengths of the perpendiculars from P and Q on the straight line, x + y = 2 respectively, then the maximum value of $\alpha\beta $ is _____.
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The diameter of the circle, whose centre lies on
the line x + y = 2 in the first quadrant and which
touches both the lines x = 3 and y = 2, is
_______ .
Correct Answer: 3
Explanation:
$ \because $ center lies on x + y = 2 and in 1st quadrant center = ($\alpha $, 2 $-$ $\alpha $)
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The number of integral values of k for which
the line, 3x + 4y = k intersects the circle,
x2
+ y2
– 2x – 4y + 4 = 0 at two distinct points is
______.
Correct Answer: 9
Explanation:
Circle x2
+ y2
– 2x – 4y + 4 = 0
$ \Rightarrow $ (x – 1)2
+ (y – 2)2
= 1
Centre: (1, 2), radius = 1
Line 3x + 4y – k = 0 intersects the circle at two distinct points.
$ \Rightarrow $ distance of centre from the line < radius
$ \Rightarrow $ k $ \in $ {7, 8, 9, ……15} since k $ \in $ I
$ \therefore $ Total 9 integral value of k.
2020
Q126
JEE Mains
Numerical
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If the curves, x2 – 6x + y2 + 8 = 0 and
x2 – 8y + y2 + 16 – k = 0, (k > 0) touch each other
at a point, then the largest value of k is ______.
Correct Answer: 36
Explanation:
C1 : x2 + y2 – 6x + + 8 = 0
C1(3, 0) and r1 = 1
C2 : x2 + y2 – 8y + 16 – k = 0
C2(0, 4) and r2 = $\sqrt k $
Two circles touch each other
$ \therefore $ C1C2 = | r1 $ \pm $ r2 |
$ \Rightarrow $ 5 = | 1 $ \pm $ $\sqrt k $ |
$ \therefore $ 1 + $\sqrt k $ = 5 or $\sqrt k $ - 1 = 5
$ \Rightarrow $ k = 16 or k = 36
So largest value of k = 36.
2019
Q127
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
A circle touching the x-axis at (3, 0) and making an intercept of length 8 on the y-axis passes through the
point :
A.
(1, 5)
B.
( 2, 3)
C.
(3, 5)
D.
(3, 10)
Correct Answer: D
Explanation:
From the above figure equation of circle is (x - 3)2 + (y - 5)5 = 52
So (3, 10) will satisfy the equation.
2019
Q128
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If the angle of intersection at a point where the two circles with radii 5 cm and 12 cm intersect is 90o, then
the length (in cm) of their common chord is :
A.
${{13} \over 5}$
B.
${{60} \over {13}}$
C.
${{120} \over {13}}$
D.
${{13} \over 2}$
Correct Answer: C
Explanation:
C1C2 = $\sqrt {{{12}^2} + {5^2}} $ = 13
Area of $\Delta $AC1C2 = ${1 \over 2}.12.5 = {1 \over 2}.13{{AB} \over 2} \Rightarrow AB = {{120} \over {13}}units$
2019
Q129
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The locus of the centres of the circles, which touch the circle, x2
+ y2
= 1 externally, also touch the y-axis and
lie in the first quadrant, is :
A.
$x = \sqrt {1 + 2y} ,y \ge 0$
B.
$y = \sqrt {1 + 2x} ,x \ge 0$
C.
$y = \sqrt {1 + 4x} ,x \ge 0$
D.
$x = \sqrt {1 + 4y} ,y \ge 0$
Correct Answer: B
Explanation:
Let the centre is (h, k) & radius is h (h, k > 0)
OP = h + 1
$\sqrt {{h^2} + {k^2}} = h + 1$
$ \Rightarrow {h^2} + {k^2} = {h^2} + 2h + 1$
$ \Rightarrow {k^2} = 2h + 1$
$ \therefore $ Locus is y2 = 2x + 1
2019
Q130
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If the circles x2
+ y2
+ 5Kx + 2y + K = 0 and 2(x2
+ y2) + 2Kx + 3y –1 = 0, (K$ \in $R), intersect at the points
P and Q, then the line 4x + 5y – K = 0 passes through P and Q, for :
$ \Rightarrow K = {1 \over {10}}$ and $ - 2K = 20K + 10$
$ \Rightarrow $ 22K = –10
$\therefore K = {{ - 5} \over {11}}$
So No value of K exists.
2019
Q131
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The line x = y touches a circle at the point (1,1). If the circle also passes through the point (1, – 3), then its
radius is :
A.
3
B.
2
C.
2$\sqrt 2 $
D.
3$\sqrt 2 $
Correct Answer: C
Explanation:
Equation of circle = (x – 1)2 + (y –1)2 + $\lambda $(y – x) = 0
Which passes through (1, –3)
So, 0 + 16 + $\lambda $(–3 – 1) = 0
16 + $\lambda $(–4) = 0
$ \therefore $ $\lambda $ = 4
Now equation of circle
(x – 1)2 + (y – 1)2 + 4y – 4x = 0
$ \Rightarrow $ x2 + y2 – 6x + 2y + 2 = 0
radius = $\sqrt {9 + 1 - 2} = 2\sqrt 2 $
2019
Q132
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
A rectangle is inscribed in a circle with a diameter
lying along the line 3y = x + 7. If the two adjacent
vertices of the rectangle are (–8, 5) and (6, 5), then
the area of the rectangle (in sq. units) is :
A.
72
B.
84
C.
56
D.
98
Correct Answer: B
Explanation:
Distance beetween point A and B is = 14 unit
As y coordinate of point A(-8, 5) and B(6, 5) are same. So line AB is parallel to the x axis.
Point O is the center of the circle and OP is the perpendicular to the line AB. And P is the mis point of line AB.
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The tangent and the normal lines at the point
( $\sqrt 3 $, 1) to the circle x2
+ y2 = 4 and the x-axis form a triangle. The area of this triangle (in
square units) is :
A.
${4 \over {\sqrt 3 }}$
B.
${1 \over {\sqrt 3 }}$
C.
${2 \over {\sqrt 3 }}$
D.
${1 \over {3 }}$
Correct Answer: C
Explanation:
Equation of tangent to the circle x2
+ y2 = 4 at point
( $\sqrt 3 $, 1) is
$\sqrt 3 $x + y = 4
Slope of this tangent (m) = - $\sqrt 3 $
$ \therefore $ Slope of the normal at point ( $\sqrt 3 $, 1) is = ${1 \over {\sqrt 3 }}$
$ \therefore $ Equation of normal at point ( $\sqrt 3 $, 1),
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The sum of the squares of the lengths of the chords
intercepted on the circle, x2 + y2 = 16, by the lines,
x + y = n, n $ \in $ N, where N is the set of all natural
numbers, is :
A.
210
B.
160
C.
320
D.
105
Correct Answer: A
Explanation:
Let the chord x + y = n cuts the circle x2 +
y2 = 16 at A and B.
$ \therefore $ Possible value of n = 1, 2, 3, 4, 5
Length of chord AB = $2\sqrt {{{\left( 4 \right)}^2} - {{\left( {{n \over {\sqrt 2 }}} \right)}^2}} $
= $2\sqrt {16 - {{{n^2}} \over 2}} $
= $\sqrt {64 - 2{n^2}} $ = ${l}$
For n = 1, ${l^2}$ = 62
For n = 2, ${l^2}$ = 56
For n = 3, ${l^2}$ = 46
For n = 4, ${l^2}$ = 32
For n = 5, ${l^2}$ = 14
$ \therefore $ Sum of square of length of chords
= 62 + 56 + 46 + 32 + 14 = 210
2019
Q137
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If a circle of radius R passes through the origin O and intersects the coordinates axes at A and B, then the
locus of the foot of perpendicular from O on AB is :
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If a variable line, 3x + 4y – $\lambda $ = 0 is such that the two circles x2 + y2 – 2x – 2y + 1 = 0 and x2 + y2 – 18x – 2y + 78 = 0 are on its opposite sides, then the set of all values of $\lambda $ is the interval :
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Let C1 and C2 be the centres of the circles x2 + y2 – 2x – 2y – 2 = 0 and x2 + y2 – 6x – 6y + 14 = 0 respectively. If P and Q are the points of intersection of these circles, then the area (in sq. units) of the quadrilateral PC1QC2 is :
A.
4
B.
6
C.
9
D.
8
Correct Answer: A
Explanation:
Area = 2 $ \times $ ${1 \over 2}$.4 = 2
2019
Q140
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
Two circles with equal radii are intersecting at the points (0, 1) and (0, –1). The tangent at the point (0, 1) to one of the circles passes through the centre of the other circle. Then the distance between the centres of these circles is :
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
A square is inscribed in the circle x2 + y2
– 6x + 8y – 103 = 0 with its sides parallel to the coordinate axes.
Then the distance of the vertex of this square which is nearest to the origin is :
A.
$\sqrt {137} $
B.
6
C.
$\sqrt {41} $
D.
13
Correct Answer: C
Explanation:
R $ = \sqrt {9 + 16 + 103} = 8\sqrt 2 $
OA $ = 13$
OB $ = \sqrt {265} $
OC $ = \sqrt {137} $
OD $ = \sqrt {41} $
2019
Q142
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The straight line x + 2y = 1 meets the coordinate axes at A and B. A circle is drawn through A, B and the origin. Then the sum of perpendicular distances from A and B on the tangent to the circle at the origin is :
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If a circle C passing through the point (4, 0) touches the circle x2 + y2 + 4x – 6y = 12 externally at the point (1, – 1), then the radius of C is :
$ \Rightarrow $ ${1 \over {\sqrt a }}$ = ${1 \over {\sqrt b }}$ + ${1 \over {\sqrt c }}$
2018
Q147
JEE Mains
MCQ
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
If a circle C, whose radius is 3, touches externally the circle,
${x^2} + {y^2} + 2x - 4y - 4 = 0$ at the point (2, 2), then the length of the intercept cut by this circle C, on the x-axis is equal to :
A.
$2\sqrt 5 $
B.
$3\sqrt 2 $
C.
$\sqrt 5 $
D.
$2\sqrt 3 $
Correct Answer: A
Explanation:
Given circle is :
x2 + y2 + 2x $-$ 4y $-$4 = 0
$\therefore\,\,\,$ its center is ($-$ 1, 2) and radius is 3 units.
Let A = (x, y) be the center of the circle C
$ \therefore $$\,\,\,$ ${{x - 1} \over 2}$ = 2 $ \Rightarrow $ x = 5 and ${{y + 2} \over 2}$ = 2 $ \Rightarrow $ y = 2
So the center of C is (5, 2) and its radius is 3
$\therefore\,\,\,$ Equation of center C is :
x2 + y2 $-$ 10x $-$ 4y + 20 = 0
$\therefore\,\,\,$ The length of the intercept it cuts on the x-axis
iCON Education HYD, 79930 92826, 73309 7282614 Mar 2026
The tangent to the circle C1 : x2 + y2 $-$ 2x $-$ 1 = 0 at the point (2, 1) cuts off a chord of length 4 from a circle C2 whose center is (3, $-$2). The radius of C2 is :
A.
2
B.
$\sqrt 2 $
C.
3
D.
$\sqrt 6 $
Correct Answer: D
Explanation:
Here, equation of tangent on C1 at (2, 1) is :
2x + y $-$ (x + 2) $-$1 = 0
Or x + y = 3
If it cuts off the chord of the circle C2 then the equation of the chord is :
x + y = 3
$\therefore\,\,\,$ distance of the chord from (3, $-$ 2) is :