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Understand what functions are and how to represent them
Learn step-by-step with practice exercises built right in.
A function is a relationship where each input has exactly one output.
Example:
For each value of , there's exactly one value of .
If , find .
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Read as: "f of x equals 2x plus 3"
Example: Find
| x | y |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 5 |
A line or curve on a coordinate plane
"The output is one more than twice the input"
Vertical Line Test: If a vertical line touches the graph at more than one point, it's NOT a function.
Solution:
Substitute into the function:
Answer:
If , find .
Solution:
Substitute :
A function is defined by . For what value of is ?
Solution:
Set the function equal to 17:
Solve:
Answer:
Check: ✓
Answer: