Find f^-1(x) for the following equation: f(x) = (12+x)/3

f^-1(x) is equivalent to the inverse of the function f(x). To solve the inverse of a function, a series of steps must be followed:
1) Write out the equation x = f(y)
This in effect is replacing all x's of the equation with y's, and vice versa.x = (12 + y)/3
2) Rearrange the equation to make y the subject.y = 3x - 12
3) Replace y with f^-1(x). This is an important final step that can easily be missed and cause loss of marks despite your ability to answer all previous parts of the question perfectly!
Final Answer =f^-1(x) = 3x - 12
TIP: Always follow these series of steps for this type of question!