化简:(1)2m-(5m-3n)+(7m-n)(2)3(2a-3b+c)-2(-2a+2b-3c)(3)ab+[3a2b-(4a2b+ab)]-4a2b+3a2
题型:解答题难度:一般来源:不详
化简: (1)2m-(5m-3n)+(7m-n) (2)3(2a-3b+c)-2(-2a+2b-3c) (3)ab+[3a2b-(4a2b+ab)]-4a2b+3a2b. |
答案
1)2m-(5m-3n)+(7m-n)=2m-5m+3n+7m-n=4m+2n; (2)3(2a-3b+c)-2(-2a+2b-3c) =6a-9b+3c+4a-4b+6c =10a-13b+9c; (3)ab+[3a2b-(4a2b+ab)]-4a2b+3a2b =ab+[3a2b-4a2b-ab]-4a2b+3a2b =ab+3a2b-4a2b-ab-4a2b+3a2b =-2a2b; |
举一反三
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