a,=0 hoac =2a
b,=0 hoac =-(2a)
c,=a2 hoac =-(a2)
d,=1 hoac = -a/a
còn lại hông bít làm
e: TH1: x<-3
A=3x-3-2(-x-3)=3x-3+2x+6=5x+3
TH2: x>=-3
A=3x-3-2(x+3)=3x-3-2x-6=x-9
g: TH1: x<1/4
B=2(3-x)-(1-4x)
=6-2x-1+4x=2x+5
TH2: 1/4<=x<3
B=2(3-x)-4x+1=6-2x-4x+1=-6x+7
TH3: x>=3
B=2(x-3)-4x+1=2x-6-4x+1=-2x-5