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Please help!!! I really need it

Please help!!! I really need it-example-1

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Answer:


\displaystyle{ {f}^( - 1) (x) = {(x - 4)}^(3) + 1}

Explanation:

Let y = f(x)


\displaystyle{y = \sqrt[3]{x - 1} + 4}

Finding an inverse, swap x and y


\displaystyle{x = \sqrt[3]{y- 1} + 4}

Then solve for y, first subtract 4 both sides


\displaystyle{ x - 4= \sqrt[3]{y- 1} + 4 - 4} \\ \\ \displaystyle{ x - 4= \sqrt[3]{y- 1} }

Cube both sides


\displaystyle{ {(x - 4)}^(3) = \left(\sqrt[3]{y- 1} \right)^(3) } \\ \\ \displaystyle{ {(x - 4)}^(3) = y - 1}

Add both sides by 1


\displaystyle{ {(x - 4)}^(3) + 1 = y - 1 + 1} \\ \\ \displaystyle{ {(x - 4)}^(3) + 1 = y}

The final y is the inverse. Hence:


\displaystyle{ {f}^( - 1) (x) = {(x - 4)}^(3) + 1}

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