-3x²-6x>2
3x²+6x+2>0
3(x²+2x+1)>1
(x+1)²>1/3
|x+1|>根号3/3
x+1<-根号3/3或x+1>根号3/3
解得,x<-1-根号3/3或x>根号3/3-1