1.下列去括号中正确的是( )
A.a-(3b-2c)=a-3b-2c
B.x3-(2x2+x-1)=x3-2x2-x-1
C.a3+(-2a+3)=a3+2a+3
D.2x2-2(x-1)=2x2-2x+2
2.化简-{-}的结果是( )
A.5x-4y B.4y-5x
C.5x+4y D.-5x-4y
3.下列各式中,去括号正确的是( )
A.a+(2b-3c+d)=a-2b+3c-d
B.a-(2b-3c+d)=a-2b-3c+d
C.a-(2b-3c+d)=a-2b+3c-d
D.a-(2b-3c+d)=a-2b+3c+d
4.化简9x-{4x-}的结果是( )
A.2x-2 B.8x+2
C.16x+2 D.2x+2
5.a3+3a2-2a=a3+(________),a-4-ab-c=(a-2b)-(________).
6.计算:6a2-4ab-4(2a2+ab)=________.
7.代数式2a+3b与代数式-6a-8b+7a的和是________.
8.若多项式11x5+16x2-1与多项式3x3+4mx2-15x+13的和不含二次项,则m等于________.
9.已知代数式(a2+a+2b)-(a2+3a+mb)的值与b的值无关,则m的值为________.