Answer:
x⁷ + 9x⁴ - 9x³ - 81
Explanation:
(f⋅g)(x) is just another way of writing f(x) ⋅ g(x).
f(x) ⋅ g(x)
(x⁴ - 9) (x³ + 9)
If you wish to simplify:
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