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解方程:(x+3)/(x+2)-(x+4)/(x+3)=(x+5)/(x+4)-(x+2)/(x+1)

题目详情
解方程:(x+3)/(x+2)-(x+4)/(x+3)=(x+5)/(x+4)-(x+2)/(x+1)
▼优质解答
答案和解析
(x+3)/(x+2)-(x+4)/(x+3)=(x+5)/(x+4)-(x+2)/(x+1)
((x+3)^2-(x+4)(x+2))/((x+3)*(x+2))=((x+5)(x+1)-(x+4)(x+2))/((x+1)(x+4))
1/(x^2+5x+6)=-3/(x^2+5x+4)
-3x^2-15x-18=x^2+5x+4
4x^2+20x+22=0
Δ=400-4*4*22=48
x=(-20±4√3)/4
x=-5±√3