Question

let f(x)=x^3+3x^2+2x. Find the derivative of the inverse of f when x=-1

Answer 1

you need to first find the inverse of \[\Large f(x)=x^3+3x^2+2x\]which will not be pretty.

Answer 2

http://www.wolframalpha.com/input/?i=inverse+of+f%28x%29%3Dx%5E3%2B3x%5E2%2B2x

I can't help explain how to find that^^

Answer 3

But, I guess you can find the slope of f when x=-1 first, and then just reflect that over the line y=x.

Answer 4

The inverse of a function is the reflection of that function across the line y=x, and the slope of any point on the inverse is simply the reciprocal of the corresponding point on the original graph. No need to find the inverse function.

Answer 5

^exactly as I said :)