x²-2x-5=0解方程

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x²-2x-5=0
x²-2x=5
x²-2x+1=6
(x-1)²梁樱山兆=6
x-1=±√6
x1=1+√6, x2=1-√橡唯丛6

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x²-2x=5
x²隐凳历+2x+1=5+1
(x+1)²粗旁=6
x+1=±√灶搜6
x=-1-√6，x=-1+√6

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x²-2x-5=0
(x-1)²-6=0
(x-1)²=6
x-1=±√6
x=1±√6

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x²-2x-5=0
x²-2x+1=6
(x-1)²=6
x-1=±√6
x=1±√6

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x=1±√6

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