find the value of d/dx(f^-1(x)) at x=2 when f(x)=2x-4
my answer :1/2
Yes, 1/2 is correct.
That is easy.
How come you were asking for the inverse of a cubic function before? That one is super hard. You have to use the Cubic Formula there.
For Linear and Quadratic functions, getting their inverses, if they exist, is relatively easy.