Question

Let f(x) = x^3 - 2x^2 + 5x - 1, and let g be the inverse function of f. What is the value of g' (9)?

Answer 1

first
\[(f^{-1})'(x)=\frac{1}{f'(f^{-1}(x))}\]

Answer 2

so first we need to find \[f^{-1}(9)=x \\ f(x)=9\]
what value of x makes x^3-2x^2+5x-1 ,9?