问题 计算题

计算:

(1)(2xy22·(﹣3xy3);

(2)(2x﹣3y)(x+2y)﹣(x+y)2

答案

解:

(1)(2xy22·(﹣3xy3),

=4x2y4·(﹣3xy3),

=﹣12x3y7

(2)(2x﹣3y)(x+2y)﹣(x+y)2

=2x2+4xy﹣3xy﹣6y2﹣x2﹣2xy﹣y2

=x2﹣xy﹣7y2

单项选择题
单项选择题