下列运算中不正确的是_刷题宝

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下列运算中不正确的是（）

A：3xy﹣（x²﹣2xy）=5xy﹣x²

B：5x（2x²﹣y）=10x³﹣5xy

C：5mn（2m+3n﹣1）=10m²n+15mn²﹣1

D：（ab）²（2ab²﹣c）=2a³b⁴﹣a²b²c

上一题下一题 0.0难度选择题更新时间:2017-03-07 02:48:59

答案(点此获取答案解析）

C

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