NAME    [Toc]    [Back]

     acosh, acoshf -- inverse hyperbolic cosine functions

LIBRARY    [Toc]    [Back]

     Math Library (libm, -lm)

SYNOPSIS    [Toc]    [Back]

     #include <math.h>

     double
     acosh(double x);

     float
     acoshf(float x);

DESCRIPTION    [Toc]    [Back]

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

RETURN VALUES    [Toc]    [Back]

     The acosh() and the acoshf() functions return the inverse hyperbolic
     cosine of x.  On the VAX and Tahoe, if the argument is less than one
     acosh() sets the global variable errno to EDOM and causes a reserved operand
 fault.

SEE ALSO    [Toc]    [Back]

     asinh(3), atanh(3), exp(3), math(3)

HISTORY    [Toc]    [Back]

     The acosh() function appeared in 4.3BSD.


FreeBSD 5.2.1			  May 6, 1991			 FreeBSD 5.2.1