Question

[x(x^2y^2-xy)-y(x^2-x^3y)]3x^2y计算,

Answer 1

原式=[x*xy*(xy-1)-y*x^2*(1-xy)]/3x^2y【估计后面是除以!】

=[x^2*y*(xy-1)+x^2*y*(xy-1)]/3x^2y

=2x^2*y*(xy-1)/3x^2y

=(2/3)*(xy-1)