Find a Formula for the Inverse of the Function

question 2

Multiple Choice

Find a formula for the inverse of the function.

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Definitions:

LastIndexOf

A method used to find the last occurrence of a specified value in a string or array, returning the index at which it was found, or -1 if it is not found.

Substring

A portion of a string or sequence of characters within a larger string.

Equals

Equals is a method typically defined in object-oriented programming languages to evaluate whether two objects are equivalent in value or state.