## Pascal, ≥ 162 bytes “Extended Pascal” (ISO standard 10206) defines that `complex` numbers are part of the language. ```pascal function s(x:complex):complex;begin s:=cmplx(0,−1)*ln(sqrt(1−x*x)+cmplx(0,1)*x)end ``` ```pascal function arcsin(protected x: complex): complex; begin arcsin := cmplx(0, −1) * ln(sqrt(1 − sqr(x)) + cmplx(0, 1) * x); end; ``` ```pascal function c(x:complex):complex;begin c:=cmplx(0,−1)*ln(sqrt(x*x−1)+x)end ``` ```pascal function arccos(protected x: complex): complex; begin arccos := cmplx(0, −1) * ln(sqrt(sqr(x) − 1) + x); end; ``` Arc tangent is already part of the language (built-in function `arctan`). ```pascal arctan(x) ```