FUNCTIONS - Describing Functions

FUNCTIONS - Describing Functions

Author: Kate Sidlo

By the end of this tutorial, you will be able to describe function graphs and function word problems using the vocabulary words at the bottom of the tutorial.  You will also be able to draw graphs to fit word problems about functions.

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1) Take notes from the tutorial video

2) Add vocabulary definitions to your vocabulary

FUNCTIONS - Describing Functions


CONTINUOUS: A set with no breaks in domain or range

DECREASING: A function that goes down as you move across the graph from left to right

DEPENDENT: A variable that is changed based on another variable. Y-variable.

DISCRETE: A set with breaks in the domain or range

DOMAIN: The set of all inputs or x-values for a function

FINITE: A set that ends. Shown on a graph with using points at the ends.

FUNCTION: A relationship where every input has one and only one output

INCREASING: A function that goes up as you move across the graph from left to right

INDEPENDENT: A variable that is changed by choice.  X-Variable.

INFINITE: A set that never ends; lasts forever. Shown on a graph using arrows at the ends.

INPUT: A term or number that is plugged into a relationship; the x-variable in an ordered pair

LINEAR: A function in the shape of a line

NON LINEAR: A function not in the shape of a line; curve

RANGE: The set of all outputs or y-values for a function.

RELATIONSHIP: A comparison of terms, variables, and/or numbers (typically an equation or inequality)

OUTPUT: A term or number that is the answer or solution to a relationship; the y-variable in an ordered pair

VERTICAL LINE TEST: A test that uses vertical lines to check if a graph is a function. Each vertical line can intersect a graph only once for a graph to be a function.