- A relation in which each element of the domain is associated with exactly one element of the codomain.
- function rule is also known as chain rule (A formula for computing the derivative of the functional composition of two or more functions.)
through this we can easily value of another variable by computing value of one variable
⇒y=2+5x
★ if x=3 then y =17
★ if x=4 then y= 22
★ if x=5 then y=27
★ if x=10 then y=52
Hope it helps!