Answer: [tex]G(F(x)) = x^3-21x^2+147x-343\\\\[/tex]
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Work Shown:
[tex]G(x) = x^3\\\\G(F(x)) = \left(F(x)\right)^3\\\\G(F(x)) = \left(x-7\right)^3\\\\G(F(x)) = \left(x-7\right)\left(x-7\right)^2\\\\G(F(x)) = \left(x-7\right)\left(x^2-14x+49\right)\\\\G(F(x)) = x\left(x^2-14x+49\right)-7\left(x^2-14x+49\right)\\\\G(F(x)) = x^3-14x^2+49x-7x^2+98x-343\\\\G(F(x)) = x^3-21x^2+147x-343\\\\[/tex]
