This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
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gives the cosine integral function Ci(z).
  • 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.
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