Question

# The equation to the locus of the midpoints of chords of the circle x2+y2=r2 having a constant length 2l is

A
B
C
D

Solution

## The correct option is B Let P(x1,y1) be a point on the locus Then P is the mid point of a chord AB of the circle x2+y2=r2 Now OP2+AP2=OA2⇒x21+y21=r2−l2 ∴ The locus of P is x2+y2=r2−l2

Suggest corrections