posting on request.
Let $a_1,a_2,a_3,.....,a_n$ are positive real numbers.
prove or disprove it,
if,
\[a_1+a_2+a_3+.....+a_n=n\]
then,
\[\sum_{cyclic}^{} \frac{a_1}{1+a_2^2}\geq \frac {n}{2}\]
Example:
$\sum_{cyclic}^{} \frac{a}{1+b^2}$ for $a,b,c$ is equal to
\[\frac{a}{1+b^2}+\frac{b}{1+c^2}+\frac{c}{1+a^2}\]
Inequality(open ended)[made by shanzeed anwar]
- nafistiham
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\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.
Using $L^AT_EX$ and following the rules of the forum are very easy but really important, too.Please co-operate.
Re: Inequality(open ended)[made by shanzeed anwar]
It's open ended because the equality is only my conjecture.
$\color{blue}{\textit{To}} \color{red}{\textit{ problems }} \color{blue}{\textit{I am encountering with-}} \color{green}{\textit{AVADA KEDAVRA!}}$
- Phlembac Adib Hasan
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Re: Inequality(open ended)[made by shanzeed anwar]
I think it may be not true for all $n$s.Re-arrangement inequality gives me such a result that may not be true for large $n$s.It's very ugly so I'm not posting it here.Now I 'll try to find out such a case that does not follow this inequality.
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