Functions

Graphs of Functions

8.1

Functions

	Definition

	It is the relation in which each object in the domain has only one image in the codomain.

Identifying functions:



One-to-one functions		Relation where the object in the domain has only one image

Many-to-one functions		Relation where more than one object is matched to the same image

One-to-many relations		Relation where the object in the domain has more than one image

Many-to-many relations		Relation where at least one object has more than one image, and more than one object has the same image

Function representation:

8.2

Graphs of Functions

	Definition

	Representation of a function with a straight line or curve on a Cartesian plane.

Constructing a table of values:

A table of values can be constructed to determine the corresponding value of the ordered pair \((x,y)\) before the graph is drawn.

Steps to draw a graph:

(i)		Construct a table of values for the selected range

(ii)		Draw and label each axis with the given scale or any suitable scale

(iii)		Plot the point \((x,y)\) for the ordered pairs from the table

(iv)		Join the points to form a straight line or a smooth curve