How to find inverse functions

The following steps can be applied to find the inverse of a function. We will go through the steps by the example f(x) = 2x + 3 to find its inverse.

Replace f(x) with y
y = 2x + 3
Write 'x' in place of 'y' and 'y' in place of  'x'
x = 2y + 3

 Solve for 'y'
2y = x - 3
y = (x - 3)/2
Replace y with f^-1(x)
f^-1(x) = (x - 3)/2
f^-1(x) is the inverse of f(x) 

Thus there are four steps in finding the inverse of a function
  • Replace f(x) with y
  • Write x in place of y and y in place of x
  • Solve for y
  • Replace y with f(x)