Functions

Wednesday, 14 March 2018

11:57 PM

A function  is a rule that assigns every element  belonging to set  a unique element  that belongs to set .

 

 - the domain

 - the codomain

 

A function  is a rule that assigns exactly one value to every element of  belonging to set ,

 

 

A function is only the same as a another function if it has the same rule and domain.

 

Example

Find the domain for .

 

Now find the range for .

 

Example

Find the domain for

Firstly,  and , as the denominator cannot be equal to zero.

 

Example

Find the domain of

Firstly, , as a number in a square root sign must be larger than or equal to zero.

This question is done the easiest through graphical means.

 

, where