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\newtheorem{theorem}{قضیه}
\theoremstyle{plain}
\newtheorem{lemma}{لم}
 \newtheorem{proposition}{گزاره} 
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\newtheorem{definition}{تعریف} 
\newtheorem{example}{مثال} 
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\newtheorem{corollary}{نتیجه} 
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\newtheorem{theorem}{ قضیه 3.3}
\label{3.3}
\begin{latin}
lemma 3.3(jensens inquality)\\
let $\mu$ be a positive measure on a  $\delta$ _aljebra $\scorpio$ in a set$\Omega $,so that $\mu(\Omega)=1$.
if f is a real function in $L^{1}(\mu)$,if $a<f(x)<b$ for all $x\in \Omega $ , and if $\phi$ is convex on$(a,b)$,then \\
$\phi(\int\limits_{\Omega} {  d\mu)\leq\int\limits_{\Omega} {   (\phi o f)d\mu $
\end{latin}\\
$\ref{3.3}$
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