# Arithmetic Course/Function Definition

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## Contents

## Function[edit]

Function is a mathematical expression representing the relation of one quantity with another quantity. For example

- Function of one variable f(x)
- Function of two variables f(x,y)
- Function of three variables f(x,y,z)

## Basic Functions[edit]

### Straight Line Function[edit]

*f(x) = x*

## Two-point form[edit]

Two points also uniquely determine a line. Given points and , we have the equation

This presentation is in the **two-point form**. It is essentially the same as the point-slope form except we substitute the expression for *m*.

### Parabola Function[edit]

*f(x) = x ^{2}*

### Hyperbole Function[edit]

*f(x) = x ^{3}*

- y = x
^{3} - x | -2 -1 0 1 2
- y | -8 -1 0 1 8
*A function of a hyperbola that goes through point (0,0)*