If a function is a bijection that is, a one-to-one correspondence we are able to find an inverse function which reverses the process.
To reset the sheet click on the rounded arrows in the top right corner
If you wanted to re-define the cubic function, say, you can input g(x)=x^3+2 into the algebra input at the bottom
Try to calculate the inverse (remember to decide on an appropriate restriction of the domain of f, g or h to ensure the function you are inverting is a bijection). Plot the inverse function (e.g. invf(x)=sqrt(x)) and see if it aligns with the trace.