∵|x2-3x|>4∴x2-3x>4 或x2-3x<-4由x2-3x>4解得x<-1或x>4,x2-3x<-4无解∴不等式|x2-3x|>4的解集是 {x|x<-1或x>4}故应填{x|x<-1或x>4}