
<A NAME=Ci>

<TITLE>Ci</TITLE></A>
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<B>CI</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>Ci</em> operator returns the Cosine Integral function. 
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syntax: </H3>
<em>Ci</em>(&lt;expression&gt;) 
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examples: </H3>
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defint(cos(t)/t,t,x,infinity); 

  - ci (x) 


on rounded; 

Ci(0.35); 

  - 0.50307556932

</TT></PRE><P>The numeric values for the operator <em>Ci</em> are computed via t
he 
power series representation, which limits the argument range. 
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