These types of functions are vey important to understand. They describe how the function preserves distinctness, and how the functions interact with both the codomain and the domain.
Injective
An injective function is a function that whenever
Example 1:
Consider the function
Example 2:
Now consider the linear function
Surjective
A surjective function is a function from
Example 1:
Let
Bijection
A function that is both Injective and Surjective is called a bijection.
Example:
Let
Non Bijective Functions
There are some functions that are neither Injective nor Surjective.
Example:
Let