Question

(ii) (x + 1 + y) (x - 1 - y)​

Answer 1

Answer:

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

=(x^2-x-xy)+(x-1-y)+(xy-y+y^2)

=x^2-x-xy+x-1-y+xy-y+y^2

=x^2+y^2-2y-1