Let $a_1,a_2,......a_n$ are positive real numbers such that $\sum_{i=1}^{n} \dfrac{1}{a_i} = 1$. Prove that,
\[ \sum_{i=1}^{n} \dfrac{a_i^2}{i} > \dfrac{2n}{n+1} \]
An exercise
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Re: An exercise
I have a problem in this,have to see the ans!(╯﹏╰)
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Re: An exercise
Wrong for $n=1$.Mehedi Hasan Nowshad wrote:Let $a_1,a_2,......a_n$ are positive real numbers such that $\sum_{i=1}^{n} \dfrac{1}{a_i} = 1$. Prove that,
\[ \sum_{i=1}^{n} \dfrac{a_i^2}{i} > \dfrac{2n}{n+1} \]
Hint
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Re: An exercise
oops! I forgot about the case for n=1. :3
"Failure is simply the opportunity to begin again, this time more intelligently."
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