Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main 20249 AprilMorning Shift
Exam
JEE Main
Year
2024
Date
9 April
Shift
Morning Shift
Subject
Mathematics
Chapter
Circle

JEE Main 2024 · 9 April · Morning Shift · Mathematics · Circle

Let a circle passing through (2,0) have its centre at the point (h,...

Let a circle passing through (2,0)(2,0) have its centre at the point (h,k)(h, k). Let (xc,yc)\left(x_c, y_c\right) be the point of intersection of the lines 3x+5y=1and(2+c)x+5c2y=13 x+5 y=1 and (2+c) x+5 c^2 y=1. If h=lim⁡c→1xc\mathrm{h}=\lim _{\mathrm{c} \rightarrow 1} x_{\mathrm{c}} and k=lim⁡c→1yc\mathrm{k}=\lim _{\mathrm{c} \rightarrow 1} y_{\mathrm{c}}, then the equation of the circle is :

Options

  1. A25x2+25y2−2x+2y−60=025 x^2+25 y^2-2 x+2 y-60=0
  2. B5x2+5y2−4x+2y−12=05 x^2+5 y^2-4 x+2 y-12=0
  3. C5x2+5y2−4x−2y−12=05 x^2+5 y^2-4 x-2 y-12=0
  4. D25x2+25y2−20x+2y−60=025 x^2+25 y^2-20 x+2 y-60=0

Correct answer

D. 25x2+25y2−20x+2y−60=025 x^2+25 y^2-20 x+2 y-60=0

Step-by-step solution

(2+c)x+5c2(1−3x5)=1x=1−c22+c−3c2,y=1−3x5=c−15(2+c−3c2)h=lim⁡c→1(1−c)(1+c)(1−c)(2+3c)=25K=lim⁡c→1c−1−5(c−1)(3c+2)=−125Centre⁡(225,−125)\begin{aligned} & (2+c) x+5 c^2\left(\frac{1-3 x}{5}\right)=1 \\ & x=\frac{1-c^2}{2+c-3 c^2}, y=\frac{1-3 x}{5}=\frac{c-1}{5\left(2+c-3 c^2\right)} \\ & h=\lim _{c \rightarrow 1} \frac{(1-c)(1+c)}{(1-c)(2+3 c)}=\frac{2}{5} \\ & K=\lim _{c \rightarrow 1} \frac{c-1}{-5(c-1)(3 c+2)}=-\frac{1}{25} \\ & \operatorname{Centre}\left(\frac{2}{25},-\frac{1}{25}\right)\end{aligned}r=(2−25)2+(0−125)2=6425+1625r=16125(x−25)2+(y+125)2=161125⇒25x2+25y2−20x+2y−60=0\begin{aligned} & r=\sqrt{\left(2-\frac{2}{5}\right)^2+\left(0-\frac{1}{25}\right)^2}=\sqrt{\frac{64}{25}+\frac{1}{625}} \\ & r=\frac{\sqrt{161}}{25} \\ & \left(x-\frac{2}{5}\right)^2+\left(y+\frac{1}{25}\right)^2=\frac{161}{125} \\ & \Rightarrow 25 x^2+25 y^2-20 x+2 y-60=0\end{aligned}$
Practice Circle on Quantrex Academy →

More from Circle

Match each entry in List-I to the correct entry in List-II and choose the correct option.… JEE Advanced 2026Consider the circle C: x^2+y^2-6x-8y-11=0 . Let a variable chord AB of the circle C… JEE Main 2026Let C be a circle having centre in the first quadrant and touching the x -axis at a… JEE Main 2026Let the line x - y = 4 intersect the circle C: (x-4)^2 + (y+3)^2 = 9 at the points Q and… JEE Main 2026Let the centre of the circle x^2 + y^2 + 2gx + 2fy + 25 = 0 be in the first quadrant and… JEE Main 2026Let P be a moving point on the circle x^2 + y^2 - 6x - 8y + 21 = 0 . Then, the maximum… JEE Main 2026Suppose that two chords, drawn from the point (1, 2) on the circle x^2 + y^2 + x - 3y = 0… JEE Main 2026Let a circle pass through the origin and its centre be the point of intersection of two… JEE Main 2026Let a circle C have its centre in the first quadrant, intersect the coordinate axes at… JEE Main 2026Let the circle x^ 2 +y^ 2 =4 intersect x -axis at the points A(a, 0), a>0 and B(b, 0) .… JEE Main 2026Let y=x be the equation of a chord of the circle C_ 1 (in the closed half-plane x ≥ 0 )… JEE Main 2026Let S=\ z ∈ ℂ:|(z-6 i)/(z-2 i)|=1. and .|(z-8+2 i)/(z+2 i)|=(3)/(5)\ . Then ∑_ z ∈ ~s… JEE Main 2026Let a circle of radius 4 pass through the origin O, the points A(- 3 a, 0) and B(0,- 2 b)… JEE Main 2026If the points of intersection of the ellipses x^ 2 +2 y^ 2 -6 x-12 y+23=0 and 4 x^ 2 +2… JEE Main 2026Let the set of all values of r , for which the circles (x+1)^ 2 +(y+4)^ 2 =r^ 2 and x^ 2… JEE Main 2026If P is a point on the circle x^ 2 +y^ 2 =4, Q is a point on the straight line 5 x+y+2=0… JEE Main 2026 Full Circle list Circle JEE Maths PYQsJEE Mathematics PYQs All JEE Main PYQs