Hi student,
we have rectangular hyperbola
xy=c
2take a general point on this in parametric P(ct, c/t)
Now tangent at point P is T=0
xy
1 + yx
1 = 2c
2So in parametric
x(c/t) + y(ct) = 2c
2x/t + ty – 2c = 0….….…...(1)
Now centre is O(0,0)
LET foot of Perpendiculer be F(h,k)
So OF

tangent
So product of slopes = -1
k/h * (-1/t
2)= -1
hence k/h= t
2 ….…..(2)
Also prependicular distance OF is

Now Put t
2=k/h in above you will get the answer
I hope the solution is clear