resposta:
Resolução:
$\,x^3\,+\,2x^2\,+\,2x\,+1\,=$ $\,x^3\,+\,1\,+\,2x^2\,+\,2x\,=$ $\,(x^3\,+\,1)\,+\,2x(x\,+\,1)\,=$ $\,(x\,+\,1)(x^2\,-\,x\,+\,1)\,+\,2x(x\,+\,1)\,=$ $\,(x\,+\,1)\left[\,(x^2\,-\,x\,+\,1)\,+\,2x\,\right]\,=$ $\,(x\,+\,1)(x^2\,+\,x\,+\,1)$
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