question_answer

Let P be any point on ellipse. If S and S" are foci of the ellipse, then locus of the centroid of triangle PSS' is a conic C whose eccentricity is

A)                

B)

C)    

D)

Correct Answer: C

Solution :

[c] Given ellipse is Thus, foci are and. Let point P on the ellipse be Let the centroid of triangle PSS' be.  and Eliminating  we get locus as or which is an ellipse For this ellipse,