问题 解答题

计算:

(1)(ab22•(-a3b)3÷(-5ab)

(2)[(x+y)2-(x-y)2]÷(2xy)

答案

(1)原式=a2b4•(-a9b3)÷(-5ab)

=

1
5
a10b6

(2)原式=[x2+2xy+y2-x2+2xy-y2]÷2xy

=4xy÷2xy

=2.

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