Question

(x+y).(x-y)+(x+y)2-(x-y)

Answer 1

Resposta:

(x+y).(x-y) + (x+y).(x+y) -2xy=

x²-xy+xy -y²+ x²+xy+xy +y² -2xy=

x²-y²+x²+2xy+y²-2xy=

2x²-y²+y²+2xy-2xy=

2x²