Math Dictionary / Input

Input

An input is the value put into a function or rule.

FunctionsGrade 6Grade 7Grade 8Algebra 1SATACT

What it means

For many functions, the input is the x-value.

Also called: x-value

Examples

If f(x) = x + 2, input 5 gives output 7
The input goes into a function machine
An ordered pair writes input first

Common mistake

A function can have only one output for each input.

Try one

Question: For f(x) = 2x, what is the output when the input is 4?

Show answer

8.

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