Equation of the line passing through the points of intersection of the parabola $x^2=8 y$ and the ellipse…

Equation of the line passing through the points of intersection of the parabola $x^2=8 y$ and the ellipse $\frac{x^2}{3}+y^2=1$ is :
  1. $y-3=0$
  2. $y+3=0$
  3. $3 y+1=0$
  4. $3 y-1=0$

Solution

$ x^2=8 y $ $ \frac{x^2}{3}+y^2=1 $ From (i) and (ii), $ \frac{8 y}{3}+y^2=1 \Rightarrow y=-3, \frac{1}{3} $ When $y=-3$, then $x^2=-24$, which is not possible. When $y=\frac{1}{3}$, then $x=\pm \frac{2 \sqrt{6}}{3}$ Point of intersection are $ \left(\frac{2 \sqrt{6}}{3}, \frac{1}{3}\right) \text { and }\left(-\frac{2 \sqrt{6}}{3}, \frac{1}{3}\right) $ Required equation of the line, $ y-\frac{1}{3}=0 \Rightarrow 3 y-1=0 $

Asked in: JEE Main 2013 (09 Apr Online)

Practice more Ellipse questions on Aicharya