Question

(PUC-SP) a expressao (x+y).(x2+y2).(x-y) é igual a
a) x4+ u4.
b) x4-y4
c) x3+xy2+x2y-y3
d) x3+xy2+x2y+y3

Answer 1

(x+y)(x-y) = $x^{2} - y^{2}$

Então temos ($(x^{2} + y^{2} )(x^2-y^2)\\Assim, x^4-y^4$

Alternativa b

Answer 2

Oie, Td Bom?!

■ Resposta: Opção B.

$= (x + y) \: . \: (x {}^{2} + y {}^{2} ) \: . \: (x - y)$

$= (x {}^{2} - y {}^{2} ) \: . \: (x {}^{2} + y {}^{2} )$

$= (x {}^{2} ) {}^{2} - (y {}^{2} ) {}^{2}$

$= x {}^{4} - y {}^{4}$

Att. Makaveli1996