Example

Evaluating (fg)(2)(f \cdot g)(2) for f(x)=x7f(x) = x - 7 and g(x)=x2+8x+4g(x) = x^2 + 8x + 4

To find the evaluated value (fg)(2)(f \cdot g)(2) for f(x)=x7f(x) = x - 7 and g(x)=x2+8x+4g(x) = x^2 + 8x + 4, begin with the computed product function (fg)(x)=x3+x252x28(f \cdot g)(x) = x^3 + x^2 - 52x - 28. Substitute x=2x = 2 into this polynomial: (fg)(2)=23+2252(2)28(f \cdot g)(2) = 2^3 + 2^2 - 52(2) - 28. Simplify the terms to get 8+4104288 + 4 - 104 - 28, which computes to 120-120. Thus, (fg)(2)=120(f \cdot g)(2) = -120.

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Updated 2026-04-29

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