Question

URGENTE 20 PONTOS: Determina A·B,sabendo que A=(x+4y)·(x-4y) e B=(x³+y³)·(x³-y³)

Answer 1

Quadrados perfeitos ... 

(x+4y).(x-4y) 

x² - 4xy + 4xy - (4y)²  =  x² - 16y² 

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$(x^{3}+y^{3}).(x^{3}-y^{3})\\\\(x^{3})^{2}-x^{3}.y^{3}+x^{3}.y^{3}-(y^{3})^{2}\\\\x^{3.2}-y^{3.2}\ =\ \boxed{\boxed{x^{6}-y^{6}}}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ok$