1. replace f(x) with y
[tex]y=4x^3+1[/tex]2. Replace every x with a y and replace every y with an x
[tex]x=4y^3+1[/tex]3. Solve for y:
[tex]\begin{gathered} 4y^3=x-1 \\ y^3=\frac{x-1}{4} \\ y=\sqrt[3]{\frac{x-1}{4}} \end{gathered}[/tex]4. Replace y with f−1(x):
[tex]f^{-1}(x)=\sqrt[3]{\frac{x-1}{4}}[/tex]