Question

Does anyone know an EASY way to find the exact value of an inverse function?

Answer 1

The best attempt you have (to my knowledge) is to replace y for x (if you're dealing with 1 independent variable) and try to solve it. Just be weary of the domain restrictions!!

Answer 2

That is just the philosophical question of what an exact value is.
For me \(\sin 33\) is as exact as \(\sin^{-1} 0.766\) or \(5^{2.5}\). Because I know I can approximate it as close as I like. So as there is an algorithm to find the value of the inverse function to an arbitrary precision, every inverse is as exact as the function itself.