This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.

# CosIntegral

 CosIntegral[z]gives the cosine integral function .
• Mathematical function, suitable for both symbolic and numerical manipulation.
• .
• CosIntegral[z] has a branch cut discontinuity in the complex z plane running from - to 0.
• For certain special arguments, CosIntegral automatically evaluates to exact values.
• CosIntegral can be evaluated to arbitrary numerical precision.
Evaluate numerically:
Evaluate numerically:
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 Scope   (6)
Evaluate for complex arguments:
Evaluate to high precision:
The precision of the output tracks the precision of the input:
Simple exact values are generated automatically:
CosIntegral can be applied to power series:
Find series expansions at infinity:
 Applications   (3)
Average radiated power for a thin linear half-wave antenna:
Plot the imaginary part in the complex plane:
Plot the logarithm of the absolute value in the complex plane:
Use FullSimplify to simplify expressions containing the cosine integral:
Use FunctionExpand to express CosIntegral through other functions:
Find a numerical root:
Obtain CosIntegral from integrals and sums:
Obtain CosIntegral from a differential equation:
Calculate the Wronskian:
Integrals:
Laplace transform:
CosIntegral can take large values for moderate-size arguments:
A larger setting for \$MaxExtraPrecision can be needed:
Nested integrals:
New in 2