# Arithmetic Course/Function Definition

## FunctionEdit

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 FunctionsEdit

### Straight Line FunctionEdit

*f(x) = x*

## Two-point formEdit

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 FunctionEdit

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

### Hyperbole FunctionEdit

*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)*