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Find (f^-1)’(a)
f(x) = 5 - 2x^3, a=7

1 Answer

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Explanation:

To find \((f^{-1})'(a)\) where \(f(x) = 5 - 2x^3\) and \(a = 7\), you'll need to follow these steps:

1. Find the inverse function of \(f(x)\).

2. Evaluate \((f^{-1})'(x)\) at the point \(a\).

Step 1: Finding the inverse function \(f^{-1}(x)\):

Let \(y = 5 - 2x^3\), then solve for \(x\):

\[y - 5 = -2x^3\]

\[\frac{5 - y}{2} = x^3\]

\[\sqrt[3]{\frac{5 - y}{2}} = x\]

So, the inverse function is:

\[f^{-1}(x) = \sqrt[3]{\frac{5 - x}{2}}\]

Step 2: Evaluate \((f^{-1})'(a)\) at \(a = 7\):

\[(f^{-1})'(a) = \frac{d}{dx}\left(\sqrt[3]{\frac{5 - x}{2}}\right)\]

Plug in \(a = 7\) to get:

\[(f^{-1})'(7) = \frac{d}{dx}\left(\sqrt[3]{\frac{5 - 7}{2}}\right) = \frac{d}{dx}(-1) = 0\]

Therefore, \((f^{-1})'(a)\) at \(a = 7\) is 0.following me

User Noltibus
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