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问题: 设不等式mx平方-2x-m+1<0对于满足-2

解答:

解:
mx^-2x-m+1<0
x^-1>0时
m<(2x-1)/(x^-1)
∵-2<m<2
∴-2<m<(2x-1)/(x^-1) 和(2x-1)/(x^-1)≥2
由-2<m<(2x-1)/(x^-1)得:
x>(-1+√7)/2 or x<(-1-√7)/2
∵x^-1>0
∴取x>1 or x<(-1-√7)/2
由(2x-1)/(x^-1)≥2得:
(1-√3)/2≤x≤(1+√3)/2
∵x^-1>0
∴无解
当x^-1<0时
m>(2x-1)/(x^-1)
∵-2<m<2 ∴ 2>(2x-1)/(x^-1)
或(2x-1)/(x^-1)≤-2
由2>(2x-1)/(x^-1)得:
x>(1+√3)/2 or x<(1-√3)/2
∵x^-1<0
∴(1+√3)/2<x or (1-√3)/2>x>-1
由(2x-1)/(x^-1)≤-2得:
(-1-√7)/2≤x≤(-1+√7)/2
∵x^-1<0
∴-1<x≤(-1+√7)/2

∴(1-√3)/2>x>-1