Inverse Functions

 

Inverse Functions





An inverse of a function is a another function that reverses the operations performed by the original function. It is used to get back the original value from the final answer we got using the first function!

Finding the inverse of a function is extremely simple. It requires only two steps!

1. Switch 'x' and 'y'( the two variables)

2. Make 'y' the subject of the equation


You have the inverse function now!


Worked example:


Here as you can see, the 'x' and 'y' variables were swapped and then we made 'y' the subject again to give us the inverse!

Many functions exist, one-one, one-many, many-one. An inverse function only exists in one-one functions, where only one 'x' value gives a single 'y' value.


Questions: Find the inverse of each of the four functions below.









Solutions:                                                                                           


















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