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问题: 解方程

根号(1+3/(x-1))+根号(1-3/(x+2))=5/2

解答:

√[1+3/(x-1)] + √[1-3/(x+2)] = 5/2

 √[1+3/(x-1)] + √[1-3/(x+2)]
= √[(x+2)/(x-1)] + √[(x-1)/(x+2)] = 5/2

令√[(x+2)/(x-1)]=y--->y + 1/y = 5/2
--->2y²-5y+2 = 0--->(y-2)(2y-1)=0--->y=2或1/2

y=√[(x+2)/(x-1)]=2时----->1+3/(x-1)=4----->x=2
y=√[(x+2)/(x-1)]=1/2时--->1+3/(x-1)=1/4--->x=-5

--->原方程的解为x=2或x=-5