# Inverse Function

The inverse function *f*^{-1} of a function *f* is the function for which f(*f*^{-1}(*x*)) = *x* for any *x*.

Inverse function is a high school-level concept that would be first encountered in a pre-calculus course covering functions. It is listed in the California State Standards for Algebra II.

### Examples

Logarithm: | The logarithm is the power to which a number (called the base) must be raised to produce a given number. For example, the logarithm of 100 with respect to the base 10 is 2. |

Matrix Inverse: | Given a matrix M, the inverse matrix is a new matrix M^{-1} that when multiplied by M, gives the identity matrix. |

Square Root: | A square root of x is a number r such that r*r = x. |

### Prerequisites

Function: | A function is a relation that uniquely associates members of one set with members of another set. The term "function" is sometimes implicitly understood to mean continuous function, linear function, or function into the complex numbers. |