Bijection

Inverse Functions Given a function , if there is a function such that which equals the identity function The function is said to be "invertible" "undoes" what "does", and vice versa Such a function is called the inverse, denoted as (the inverse of ) The notation is not to be confused with an exponent In some cases the inverse of a function can be found through algebraic methods CONSIDER: Given to determine we must find a functions that must undo But, recall the set of outputs from , to undo we take Thus Observe that: Not every function has an inverse CONSIDER: But is not a function. An inverse only exists when different inputs in the domain always yield different outputs in the range Such functions are called one-to-one