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gives the arc secant sec^(-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 outside the interval -1 to 1, the results are always in the range 0 to pi, excluding pi/2.
  • For certain special arguments, ArcSec automatically evaluates to exact values.
  • ArcSec can be evaluated to arbitrary numerical precision.
  • ArcSec automatically threads over lists.
  • ArcSec[z] has a branch cut discontinuity in the complex z plane running from -1 to +1.
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