解不等式(x2-3x+2)/(x2-5x-6)>(x2-5x-6)/(x2-3x+2)

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解不等式(x2-3x+2)/(x2-5x-6)>(x2-5x-6)/(x2-3x+2)
解不等式(x2-3x+2)/(x2-5x-6)>(x2-5x-6)/(x2-3x+2)

解不等式(x2-3x+2)/(x2-5x-6)>(x2-5x-6)/(x2-3x+2)
(x2-3x+2)/(x2-5x-6)>(x2-5x-6)/(x2-3x+2)
(x-1)(x-2)/(x-6)(x+1)>(x-6)(x+1)/(x-1)(x-2)
(x-1)(x-2)/(x-6)(x+1)-(x-6)(x+1)/(x-1)(x-2)>0
[(x-1)(x-2)]^2-[(x-6)(x+1)]^2/ (x-6)(x+1)(x-1)(x-2)>0
[(2x+8)(2x^2-8x-4)] / (x-6)(x+1)(x-1)(x-2)>0且x不等于6,-1,2,1
(x+4)(x^2-4x-2) / (x-6)(x+1)(x-1)(x-2)>0且x不等于6,-1,2,1
即(x+4)(x^2-4x-2) (x-6)(x+1)(x-1)(x-2)>0,(x^2-4x-2)=0得出x1=2+√6,x2=2-√6
(x+4)(x^2-4x-2) (x-6)(x+1)(x-1)(x-2)>0利用穿线法得出
X属于(-4,-1)或(2-√6,1)或(2,2+√6)

答案:-46

(x^2-3x+2)/(x^2-5x-6)>(x^2-5x-6)/(x^2-3x+2) ①
[(x-3/2)^2-(1/2)^2]/[(x-5/2)^2-(7/2)^2]>[(x-5/2)^2-(7/2)^2]/[(x-3/2)^2-(1/2)^2]
因分母不能为0
所以 (x-3/2)^2-(1/2)^2≠0...

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答案:-46

(x^2-3x+2)/(x^2-5x-6)>(x^2-5x-6)/(x^2-3x+2) ①
[(x-3/2)^2-(1/2)^2]/[(x-5/2)^2-(7/2)^2]>[(x-5/2)^2-(7/2)^2]/[(x-3/2)^2-(1/2)^2]
因分母不能为0
所以 (x-3/2)^2-(1/2)^2≠0 ② 且 (x-5/2)^2-(7/2)^2≠0 ③
解② x-3/2≠1/2 且 x-3/2≠-1/2
x≠2 且 x≠1
解③ x-5/2≠7/2 且 x-5/2≠-7/2
x≠6 且 x≠-1
综上:x≠-1 , x≠1 , x≠2 , x≠6
当 x<-1 时 (x-3/2)^2-(1/2)^2>0 , (x-5/2)^2-(7/2)^2>0
[(x-3/2)^2-(1/2)^2]*[(x-5/2)^2-(7/2)^2]>0 ④
将①式两边同时乘以④得:
x^2-3x+2>x^2-5x-6
x>-4
即:-4当 -10 , (x-5/2)^2-(7/2)^2<0
[(x-3/2)^2-(1/2)^2]*[(x-5/2)^2-(7/2)^2]<0 ⑤
将①式两边同时乘以⑤得:
x^2-3x+2 x<-4
即:x无解
当 1 [(x-3/2)^2-(1/2)^2]*[(x-5/2)^2-(7/2)^2]>0 ⑥
将①式两边同时乘以⑥得:
x^2-3x+2>x^2-5x-6
x>-4
即:1当 20 , (x-5/2)^2-(7/2)^2<0
[(x-3/2)^2-(1/2)^2]*[(x-5/2)^2-(7/2)^2]<0 ⑦
将①式两边同时乘以⑦得:
x^2-3x+2 x<-4
即:x无解
当x>6 时 (x-3/2)^2-(1/2)^2>0 , (x-5/2)^2-(7/2)^2>0
[(x-3/2)^2-(1/2)^2]*[(x-5/2)^2-(7/2)^2]>0 ⑧
将①式两边同时乘以⑧得:
x^2-3x+2>x^2-5x-6
x>-4
即:x>6
综上:-46

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(x2-3x+2)/(x2-5x-6)>(x2-5x-6)/(x2-3x+2)
原不等式整理后得
x^2-3x+1>0
假如 x^2-3x+1=0
求得x的根为:
x=(3±√5)/2
即有 x1=(3+√5)/2
x...

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(x2-3x+2)/(x2-5x-6)>(x2-5x-6)/(x2-3x+2)
原不等式整理后得
x^2-3x+1>0
假如 x^2-3x+1=0
求得x的根为:
x=(3±√5)/2
即有 x1=(3+√5)/2
x2=(3-√5)/2
经检验,x1、x2都是 x^2-3x+1=0的解。
x1、x2都>0 x1>x2
∴ 经检验原不等式的解是 x>(3-√5)/2

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