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[不等式] 证明一个不等式

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TSC999 Posted 2021-3-7 20:02 |Read mode
Last edited by TSC999 2021-3-7 20:25若 \(a_1, a_2, \cdots, a_n>0 \), 证明不等式:

需要证明的.png

\(a_1=a_2= \cdots=a_n \) 时取等号。

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kuing Posted 2021-3-7 20:31
中间显然不成立,令 a2=a3=...=an->0 即知;
右边反例:n=5, a=b=c=1, d=e=2

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 Author| TSC999 Posted 2021-3-8 08:56
Last edited by TSC999 2021-3-8 09:38回复 2# kuing

你说的对,右边那个确实不成立。去掉它,下式可以证明成立,不知对不对?
需要证明的.png

另外,对于三元的情况,下式这个证明对否?

证明三元情况.png

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kuing Posted 2021-3-8 14:44
回复 3# TSC999

那这个就变成常识了……

1楼右边 n=3, 4 是成立的

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