Inverse Function f(x)= 5 -1/3x

Mathematics · High School · Mon Jan 18 2021

Answered on

Given the function:

f(x) = 5 - ⅓x

Determine the inverse function.

Solution:

Inverse function is written in the form f^-1(x), hence to convert a function into an inverse function, we equate the value of f(x) to y, then interchange y and x, and lastly solve for x. To clearly understand this, please refer to the solution below.

f(x) = 5 - ⅓x

y = 5 - ⅓x

x = 5 - ⅓y

Transpose -⅓y and x to the opposite side of their equations, hence we must take note that in transposing a number, the sign changes.

⅓y = 5 -x

Multiply both sides by 3 in order to cancel out ⅓y.

(3) ⅓y = 5 -x  (3)

y = 15 - 3x

Final answer:

f^-1(x) = 15 - 3x