1.、把3-2[2a-2(a-3)]化简,所得结果应为( -9)2.去括号:(a-b)-(c-d)=a-b-c+d3.去括号:a-(-a+c-b)=2a-c+b4..将(a+1)-(-b-c)去括号得a+b+c+1
1、解:原式=3-2[2a-2a+6] =3-12 =-92、解:原式=a-b-c+d3、解:原式=a+a-b+c =2a-b+c4、解:原式=a+1+b+c =a+b+c+1