百度作业网写纸上发图
来源：学生作业帮 编辑：百度作业网作业帮 分类：数学作业 时间：2024/05/05 00:41:29
写纸上发图
(x+1/x)²=x²+2+1/x²=9
x²+1/x²=7
(x-1/x)²=x²-2+1/x²=7-2=5
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x²-x-2=0且x²+2x+1≠0
(x-2)(x+1)=0且(x+1)²≠0
x=2
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a/(a+1)²+1/(a+1)²=(a+1)/(a+1)²=1/(a+1)=1/(1+1/2)=2/3
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x²-1=0且x+1≠0
(x-1)(x+1)=0且x≠-1
x=1
x²+1/x²=7
(x-1/x)²=x²-2+1/x²=7-2=5
-------------------------
x²-x-2=0且x²+2x+1≠0
(x-2)(x+1)=0且(x+1)²≠0
x=2
-------------------------
a/(a+1)²+1/(a+1)²=(a+1)/(a+1)²=1/(a+1)=1/(1+1/2)=2/3
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x²-1=0且x+1≠0
(x-1)(x+1)=0且x≠-1
x=1