KVPY2017MathematicsEllipse
An ellipse x ² a ² + y ² ~b ² =1, a > b and the parabola x ²=4( y + b ) are such that the two foci of the ellipse and the end points of the latus rectum of parabola are the vertices of a square. The eccentricity of the ellipse is
Options
- A1 13
- B2 13
- C1 11
- D2 11
Correct answer
B. 2 13
Step-by-step solution
As it is square array l ae =2 4= ( ae -2)²+(1- b )² ~b =-3 ~b =5 a ²=13 a ²=29 ( from realation b ²= a ² (1- e ² ) . ae =2 e = 2 13 array