IMTAN function /text/scalc/01/func_imtan.xhp
IMTAN function tangent;complex number

IMTAN function

Returns the tangent of a complex number. The tangent of a complex number can be expressed by:
IMTAN equation IMTAN(Complex_number) Complex_number is a complex number whose tangent is to be calculated.

=IMTAN("4-3i")
returns 0.00490825806749606-1.00070953606723i. =IMTAN(2)
returns -2.18503986326152 as a string.
IMTAN wiki page.