
<A NAME=Chi>

<TITLE>Chi</TITLE></A>
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<B>CHI</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>Chi</em> operator returns the Hyperbolic Cosine Integral function. 
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syntax: </H3>
<em>Chi</em>(&lt;expression&gt;) 
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examples: </H3>
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defint((cosh(t)-1)/t,t,0,x); 

  - log(x) + psi(1) + chi(x)


on rounded; 

Chi(0.35); 

  - 0.44182471827

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