freebsd man page for acoshl

ACOSH(3)						   BSD Library Functions Manual 						  ACOSH(3)

NAME
     acosh, acoshf, acoshl -- inverse hyperbolic cosine functions

LIBRARY
     Math Library (libm, -lm)

SYNOPSIS
     #include <math.h>

     double
     acosh(double x);

     float
     acoshf(float x);

     long double
     acoshl(long double x);

DESCRIPTION
     The acosh(), acoshf(), and acoshl() functions compute the inverse hyperbolic cosine of the real argument x.  For a discussion of error due to
     roundoff, see math(3).

RETURN VALUES
     These functions return the inverse hyperbolic cosine of x.  If the argument is less than 1, acosh() raises an invalid exception and returns
     an NaN.

SEE ALSO
     asinh(3), atanh(3), exp(3), fenv(3), math(3)

HISTORY
     The acosh(), acoshf(), and acoshl() functions appeared in 4.3BSD, FreeBSD 2.0, and FreeBSD 10.0, respectively.

BSD
								   June 9, 2013 							       BSD