(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Assume the function f(x)=x^3+x has an inverse in R. Determine d/dx(f^-1(x)) at x=2.

2. Relevant equations

(f^-1(x))'=1/f'(f^-1(x))

3. The attempt at a solution

y'=3x^2+1

(f^-1(x))'=1/(3y^2+1)

now i substitute f^-1(2), y=10, into the equation but do not get the correct answer. I suspect that the mistake i am making is becuase i do not fully understand the question. Any help is greatly appreciated.

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# Homework Help: Inverse Derivative Question

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