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<H3 CLASS="subsection"><A NAME="htoc121">2.12.11</A>  Zeros of an expression : <TT>zeros</TT></H3><P><A NAME="@default172"></A>
<TT>zeros</TT> takes as argument an expression depending on <I>x</I>.<BR>
<TT>zeros</TT> returns a list of values of <I>x</I> where the expression
vanishes. The list may be incomplete in exact mode if the expression
is not polynomial or if intermediate
factorizations have irreducible factors of order strictly
greater than 2.<BR>
In real mode, (complex box unchecked in the Cas configuration
or <TT>complex_mode:=0</TT>), only reals zeros are returned. In
(<TT>complex_mode:=1</TT>) reals and complex zeros are returned. See
also <TT>cZeros</TT> to get complex zeros in real mode.<BR>
Input in real mode : 
</P><DIV CLASS="center"><TT>zeros(x</TT><CODE><TT>^</TT></CODE><TT>2+4)</TT></DIV><P> 
Output :
</P><DIV CLASS="center"><TT>[]</TT></DIV><P> 
Input in complex mode : 
</P><DIV CLASS="center"><TT>zeros(x</TT><CODE><TT>^</TT></CODE><TT>2+4)</TT></DIV><P> 
Output :
</P><DIV CLASS="center"><TT>[-2*i,2*i]</TT></DIV><P> 
Input in real mode : 
</P><DIV CLASS="center"><TT>zeros(ln(x)</TT><CODE><TT>^</TT></CODE><TT>2-2)</TT></DIV><P> 
Output :
</P><DIV CLASS="center"><TT>[exp(sqrt(2)),exp(-(sqrt(2)))]</TT></DIV><P> 
Input in real mode : 
</P><DIV CLASS="center"><TT>zeros(ln(y)</TT><CODE><TT>^</TT></CODE><TT>2-2,y)</TT></DIV><P> 
Output :
</P><DIV CLASS="center"><TT>[exp(sqrt(2)),exp(-(sqrt(2)))]</TT></DIV><P> 
Input in real mode : 
</P><DIV CLASS="center"><TT>zeros(x*(exp(x))</TT><CODE><TT>^</TT></CODE><TT>2-2*x-2*(exp(x))</TT><CODE><TT>^</TT></CODE><TT>2+4)</TT></DIV><P> 
Output :
</P><DIV CLASS="center"><TT>[[log(sqrt(2)),2]</TT></DIV><HR>
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