H Alg Ch 2

Function

Pairing between two sets in which each element of the first set is paired with one element of the second set

Relation

Pairing between two sets

Independent variables

Input

Dependant variables

Output

Discrete graph

Isolated points, example: number people, amounts of money

Continuous graph

Connected points, example: time since league, number of gallons on floor

Onto functions

All elements of the range is used in a pairing with elements of domain

1-1 Functions

Each element of domain is paired with unique element of range

Is function linear?

If to the first power, the graph will be a line

Increasing function

As X increases, Y increases

Decreasing function

As X increases, Y decreases

Constant rate of change

Slope

Slope-intercept form

y=m x+ b

Modified point slope form

y=m (x-x1) +y1

Parallel lines

Have the same slope, all vertical lines

Perpendicular lines

The product of slope is -1, slopes are opposite reciprocals