月单行
幼苗
共回答了17个问题采纳率:64.7% 举报
(1)原式=12-18+7-15=-14;
(2)原式=-6-9=-15;
(3)原式=-1-[1/4×(2−9)=-1+
7
4]=[3/4];
(4)原式=[7/9÷
7
15−
1
3×16=
5
3−
16
3=−
11
3];
(5)原式=(5+2)xy2+(2-3)x2y+(-1-2)=7xy2-x2y-3;
(6)原式=5a-3b-3a+6b=2a+3b;
(7)原式=5x2-[3x+2x-6-4x2]
=5x2-3x-2x+6+4x2
=9x2-5x+6.
1年前
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