Question

(x+y)(x-y)+(x-y)^2-(6x^2×y÷2y-2xy^2÷2y)其中x=-3,y=1/3

Answer 1

答：

(x+y)(x-y)+(x-y)^2-(6x^2×y÷2y-2xy^2÷2y)

=x^2-y^2+x^2-2xy+y^2-(3x^2-xy)

=2x^2-2xy-3x^2+xy

=-x^2-xy

=-x(x+y)

=-(-3)*(-3+1/3)

=-9+1

=-8