-2(3a+2b)+3(a-b)
=-6a-4b+3a-3b
=-3a-7b
=-3*(-1)-7*1/7
=3-1
=2
先化简,再求值:-2(3a+2b)+3(a-b),其中a=-1,b=1/7
先化简,再求值:-2(3a+2b)+3(a-b),其中a=-1,b=1/7
数学人气:868 ℃时间:2019-11-02 13:11:50
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