x/(x+1)-3x>=0 (x-3x^2-3x)/(x+1)>=0 (3x^2+2x)/(x+1)<=0 x<-1 [-2/3;0]</p>
x/(x+1)+2>=0 (3x+2)/(x+1)>=0 x<-1 U x>=-2/3
x<-1 U [-2/3;0]</p>
x/(x+1)-3x+x/(x+1)+2=3x+2
2x/(x+1)-6x=0
2x-6x^2-6x=0
6x^2+4x=0 x=0 x=-2/3
x>0
3x-x/(x+1)+x/(x+1)+2=3x+2
0=0 x>0
]-1;-2/3[
3x-x/(x+1)-x/(x+1)-2=3x+2
2x/(x+1)+4=0
x/(x+1)+2=0
x+2x+2=0 x=-2/3
ответ x=-2/3 x>=0