Q. If the shortest distance of the parabola y² = 4x from the centre of the circle x² + y²– 4x- 16y + 64 = 0 is d, then d² is equal to:
( JEE mains 2024)
A. 16
B. 24
C. 20
D. 36
Ans:- (c)
Equation of normal to parabola
y = mx-2m-m³
this normal passing through center of circle (2, 8)
8=2m-2m -m³
m =-2
So point P on parabola (am², -2am) = (4, 4)
And
C = (2, 8)
PC = √4+16=√20
d² = 20
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