Prove that for spherical mirrors the product of the distance of the object and the image to the
principal focus is always equal to the square of the principal focal length.

Answer

A, B, C, D

Explanation

Using `1/v+1/u=1/f`
`:. (1)/(-(y+f))+(1)/(-(x+f))=(1)/(-f)`
Solving this equation , we get
`xy=f^(2)`.