Question

先合并同类项在求值.5ab-4a^2b^2-8ab^2+3ab-ab^2+4a^2b^2其中a=1,b=-1

Answer 1

原式=5ab-4a^2b^2-8ab^2+3ab-ab^2+4a^2b^2

=8ab-9ab^2

将a=1,b=-1代入,

则,原式=-8-9=-17.