Function Notation and Evaluation

Notation

f(x) = 2x + 3 means the function named f multiplies the input by 2 then adds 3.

f: x → 2x + 3 is the same rule.

Evaluation

Replace x with the given value.

Example: If f(x) = x2 - 4x + 1, find f(3).
f(3) = 32 - 4(3) + 1 = 9 - 12 + 1 = -2

Example: If g(x) = 5/x, find g(-2).
g(-2) = 5/(-2) = -2.5

Discussion

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Related Exercises

Evaluate functions

Given f(x) = 3x - 2, g(x) = x2 + 1, h(x) = 4/x, find:f(4)g(-3)h(2)f(-1)g(0)h(-4)

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