Question

Efetue e simplifique (1+x)(1-x)-(1+x)

Answer 1

(1+x)(1-x)-(1+x)

1-x+x-x²-1-x=0

-x²-x=0 (-1)

x²+x=0

x(x+1)=0

x=0

x+1=0

x=-1

S=(-1, 0)