Step 1: Determine if the function has an inverse using the horizontal line test.
Horizontal Line Test: a horizontal line through the function only touches it at one point
Step 2: Replace f(x) with y and switch x and y.
Step 3: Solve for y.
Step 4: Replace y with f^-1(x).
Step 5: Restrict the domain and range of the inverse such that the domain of f(x) is the same as the range of inverse of f(x) and the domain of inverse of f(x) is the range of f(x).