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Explanation:
This is a piecewise function as it is composed of two pieces.
The equation for f(x) depends on what x is. Specifically whether it is even or odd.
If x is even, then f(x) = x^2-4. If x is odd, then f(x) = 3x-2
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f(4) means f(x) when x = 4. We have an even number input for x, so we'll go with f(x) = x^2-4
f(x) = x^2 - 4
f(4) = 4^2 - 4
f(4) = 16 - 4
f(4) = 12
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When x = 5, x is now odd, so use f(x) = 3x-2
f(x) = 3x-2
f(5) = 3(5) - 2
f(5) = 15 - 2
f(5) = 13
