Question

4xy-3x^2-3xy-2y+2x^2其中x=-1,y=1.(求代数式的值)

Answer 1

4xy-3x^2-3xy-2y+2x^2其中x=-1,y=1带入代数式得：

4xy-3x^2-3xy-2y+2x^2

=xy-x^2-2y

=1*(-1)-（-1)^2-2*1

=-1-1-2

=-4