How do you find the inverse of $f(x)=root5(5x+4)$ ?

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Answer 1 · 2017-02-24T18:39:01

$f^-1 = (x^5-4)/5$

Let $y = f(x): y = root(5)(5x+4)$

Swap $y$ for $x$ and $x$ for $y$ : $x = root(5)(5y+4)$

Remember that $root(5)( ) = ( )^(1/5)$ so $x = (5y+4)^(1/5)$

Solve for $y$ .

The inverse function $f^-1 = (x^5-4)/5$

How do you find the inverse of f(x)=root5(5x+4)f(x)=root5(5x+4)?