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

f(x) = 2x^{2}+ 4e^{(5x)}

is invertible. Give the slope of the normal line to the graph of f^{-1}at x = 4.

2. Relevant equations

(Given in question)

3. The attempt at a solution

I don't know how to solve this question. But , I found the following:-

f(4) = 32 + 4e^{20}

let y = f^{-1}(x), then

dy/dx = 1/f ' (y)

f ' (x) = 4x + 20e^{(5x)}

Hence, dy / dx = 1/(4y + 20e^{(5y)})

I don't know if I am heading in the right direction.

Please help!!

Thank you.

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# Homework Help: Slope of normal to a given function's inverse

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