Search 75,761 tutors
FIND TUTORS
Ask a question
0 0

Find the inverse function of f(x)=x^3+5

Tutors, please sign in to answer this question.

2 Answers

f-1(x) denotes the inverse, not 1/f(x),

Let x  =  (f-1(x))^3  + 5

x  -  5  =  (f-1(x))^3

f-1(x) = (x - 5)^(1/3)

y = x3 + 5 . Solve this equation for x:
x3 = y - 5 ---> (x3)1/3 = (y - 5)1/3 ---> x = (y - 5)1/3 , now type y instead of x, and x instead of y
                                                       y = (x - 5)1/3 
  in term of f(x) ---->                   f-1(x) = (x - 5)1/3