Example

Evaluating (fg)(2)(f \cdot g)(2) for f(x)=x+2f(x) = x + 2 and g(x)=x23x4g(x) = x^2 - 3x - 4

To evaluate the product function (fg)(2)(f \cdot g)(2) for f(x)=x+2f(x) = x + 2 and g(x)=x23x4g(x) = x^2 - 3x - 4, first determine the general product function, which is (fg)(x)=x3x210x8(f \cdot g)(x) = x^3 - x^2 - 10x - 8. Next, substitute x=2x = 2 into this resulting polynomial: (fg)(2)=232210(2)8(f \cdot g)(2) = 2^3 - 2^2 - 10(2) - 8. Simplify the expression according to the order of operations: 842088 - 4 - 20 - 8, which sums to 24-24. Thus, (fg)(2)=24(f \cdot g)(2) = -24.

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Updated 2026-04-29

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