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Inverse Functions
Review: Definition of a Function
A function is a set of ordered pairs where for every x-value there is a unique y-value.
Graphically: Use the vertical line test to determine if the graph is a function.
Determine if the following graphs are functions?
One to One Functions (1 – 1 functions)
A function is said to be one to one if each y-value corresponds to only one x-value.
Graphically: Use the horizontal line test to determine if the following functions are
One to One Functions.
Determine if the following funcitons are One to One Functions
What is an Inverse Function?
Only one-to-one functions have inverse functions. A function and its inverse can be
described as the "DO" and the "UNDO" functions. A function takes a starting value, performs
some operation on this value, and creates an output answer. The inverse of this function takes
the output answer, performs some operation on it, and arrives back at the original function's
starting value.
