Given function is .

Replace with y.

Next Switch x for y and y  for x.

.

Next solve for y :

           (Multiply each side by 3)

      (Apply distributive property: )

               (Cancel common terms)

                               (Multiply: )

           (Subtract 6 from each side)

                 (Apply additive inverse property: )

                      (Apply additive identity property: )

        (Multiply each side by negative one)

  (Apply distributive property: )

                   (Product of two same signs is positive)

                               (Product of two different signs is negative)

 The value of .

Write in function notation,using to represent the invrse of the function f.

"Y " value substitute in above function,

.

The invrse of the function is  .