Question

The inverse of function f(x) = x^3 + 2 is ____________

(a) f^ -1 (y) = (y – 2)^ 1/2

(b) f^ -1 (y) = (y – 2)^ 1/3

(c) f^ -1 (y) = (y)^ 1/3

(d) f^ -1 (y) = (y – 2)

The question was asked in class test.

This interesting question is from Functions in chapter Basic Structures: Sets, Functions, Sequences, Sums and Matrices of Discrete Mathematics

Answer 1

Correct option is (b) f^ -1 (y) = (y – 2)^ 1/3

For explanation I would say: To find the inverse of the function equate f(x) then find the value of x in terms of y such that f^ -1 (y) = x.