Consider the function f(x) = x |x| + 1. Find f^-1(8).

It isn't obvious how to find an expression for f^-1(x) by switching the variables and trying to solve for y, and you don't need to do this. Remember the property of inverses that says f^-1(y)=x ifff(x)=y. So f^-1(8)=x ifff(x)=8. What does the value of x need to be