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\author{ghidouche}
\title{Paper1_kahina}
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\section{Root finding problem}
we consider a polynomial 
$p(x)=\sum{a_{i}x^{i}}=a_{n}\prod(x-\alpha_{i}), a_{0} a_{n}\neq0,$
of degree \textit{n}having coefficients in the complex \textit{c} and zeros \alpha_{i},\textit{i=1,...,n}.
the root finding problem consiste to find all n root of \textit{p(x)}. the problem of finding a root is equivalent to the problem of finding a fixed-point. To see this consider the fixed-point problem of finding the
n-dimensional vector x such that

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