x²-2x-4<[x-3]-[x+1] []为绝对值 谁会解
问题描述:
x²-2x-4<[x-3]-[x+1] []为绝对值 谁会解
答
x^2-2x-4 < |x-3| - |x+1|如果x<-1:x^2-2x-4 < 3-x +(x+1) = 4x^2-2x-8<0(x+2)(x-4)<0-2<x<4又:x<-1∴-2<x<-1如果-1≤x≤3:x^2-2x-4 < 3-x -(x+1) = 2-2xx^2<6-√6<x<√6又:-1≤x≤3∴-1≤x≤√6...