閱讀下列內容 幾個不等于零的書的乘積,積的符號由負因數(shù)的個數(shù)決定,例如:考查代數(shù)式(x-1)(x-2) 的值 當x<1時,x-1<0,x-2<0 所以 (x-1)(x-2)>0 當1<x<2時,x-1>0,x-2<0 所以 (x-1)(x-2)<0 當x>2時,x-1>0,x-2>0 所以 (x-1)(x-2)>0 所以當x<1或x>2時,(x-1)(x-2)>0,當1<x<2時,x-1>0,x-2<0時,(x-1)(x-2)<0 填寫下表:(用正負號填空) x<-2 -2<x<-1 -1<x<3 3<x<4 4<x<5 x<5x+2 - + + + + +x+1 - - + + + +x-3 - - - + + +x-4 - - - - + +x-5 - - - - - +(x+2)(x+1)(x-3)(x-4)(x-5) - + - + - +根據(jù)以上填表寫出x 時,(x+2)(x+1)(x-3)(x-4)(x-5)<0 請你運用所發(fā)現(xiàn)的規(guī)律,寫出當x 時,(x-8)(x-9)(x-10)(x-11)〉0