1 a+[a+b+c]-[b-a]=3a+c
2 a×{b+c}-a[b-c]=2ac
3 {[a÷b]×{b÷a+1]}×{b÷a}=1
4 a+b-{c×2a}-ac+3[ab+ac}=a+b+3ab
5 {a+b+c}²+1=a²+b²+c²+2ab+2ac+2bc+1
6 {a+b}{a-b}+2a{3b-2b]=a²+b²-2ab
汗打了那么长时间终于打出来了,给个分数吧
呵呵!答案就在这
1 a+[a+b+c]-[b-a]=3a+c
2 a×{b+c}-a[b-c]=2ac
3 {[a÷b]×{b÷a+1]}×{b÷a}=1
4 a+b-{c×2a}-ac+3[ab+ac}=a+b+3ab
5 {a+b+c}²+1=a²+b²+c²+2ab+2ac+2bc+1
6 {a+b}{a-b}+2a{3b-2b]=a²+b²-2ab
a+b+(b-a)-b-a
=a+{a-d+a-d}-b
=a+a-d+a-d-b
=3a-(-2d)-b
1.2x-(x+3y)-(-x-y)-(x-y)=______.
2.2x+2y-[3x-2(x-y)]=______.
3.5-(1-x)-1-(x-1)=______.
4.( )+(4xy+7x2-y2)=10x2-xy.
5.(4xy2-2x2y)-( )=x3-2x2y+4xy2+y3