Consider the circle . Let a variable chord AB of the circle C subtend a right angle at the origin. If the locus of the foot of the perpendicular drawn from the origin on the chord AB is the circle , then is equal to ________.
← JEE Main 2026 · 8 Apr · Shift 2
MathematicsInteger+4 / -1Question 24 of 75
JEE Main 2026 · 8 Apr · Shift 2, Mathematics question 24
Answer and worked solution
Official answer: 18
Chord with foot (h, k). Its equation is , with .
Right angle at O. Homogenise the circle with ; the and coefficients must add to zero:
Locus. : , , .
Answer. .