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Input → Process → Output
Input → Process → Output
A function is like a machine: put a number in, get a number out. f(x) = 2x + 3 means "double the input and add 3". So f(5) = 2(5) + 3 = 13. The inverse function f⁻¹(x) does the opposite - it undoes what f did!
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Quiz · Question 1 of 10
If f(x) = x² − 1, what does f(3) equal?
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