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based on an earlier version of the Wolfram Language.
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gives the arc cosine cos^(-1)(z) of the complex number z.
  • Mathematical function, suitable for both symbolic and numerical manipulation.
  • All results are given in radians.
  • For real z between -1 and 1, the results are always in the range 0 to pi.
  • For certain special arguments, ArcCos automatically evaluates to exact values.
  • ArcCos can be evaluated to arbitrary numerical precision.
  • ArcCos automatically threads over lists.
  • ArcCos[z] has branch cut discontinuities in the complex z plane running from -∞ to -1 and +1 to +∞.
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