解方程:1/(x+2)+1/(x-2)=1 3x/(x²-1)+(x²-1)/3x=5/2

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解方程:1/(x+2)+1/(x-2)=13x/(x²-1)+(x²-1)/3x=5/2解方程:1/(x+2)+1/(x-2)=13x/(x²-1)+(x²-1

解方程:1/(x+2)+1/(x-2)=1 3x/(x²-1)+(x²-1)/3x=5/2
解方程:1/(x+2)+1/(x-2)=1 3x/(x²-1)+(x²-1)/3x=5/2

解方程:1/(x+2)+1/(x-2)=1 3x/(x²-1)+(x²-1)/3x=5/2
1)两边同时乘以(x+2)(x-2)
x-2+x+2=x^2-4
x^2-2x-4=0
x=1±√5
经检验,它们都是原方程的根
2) 令t=3x/(x^2-1)
方程化为t+1/t=5/2
t^2+5t/2+1=0
(t+2)(t+1/2)=0
t=-2,-1/2
当t=-2时,3x/(x^2-1)=-2,得2x^2+3x-2=0,(2x-1)(x+2)=0,得x=1/2,-2
当t=-1/2时,3x/(x^2-1)=-1/2,得:x^2+6x-1=0,得x=-3±√10
经检验,以上4个都为原方程的根.

令t=3x/(x^2-1)
方程化为t+1/t=5/2
t^2+5t/2+1=0
(t+2)(t+1/2)=0
t=-2, -1/2
当t=-2时,3x/(x^2-1)=-2, 得2x^2+3x-2=0, (2x-1)(x+2)=0,得x=1/2, -2
当t=-1/2时,3x/(x^2-1)=-1/2,得:x^2+6x-1=0, 得x=-3±√10
经检验,以上4个都为原方程的根。