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Manual Reference Pages  - ACOSH (3)

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NAME

acosh, acoshf, acoshl - inverse hyperbolic cosine function

CONTENTS

Synopsis
Description
Errors

SYNOPSIS

#include <math.h> 



double acosh(double x); 




float acoshf(float x); 




long double acoshl(long double x); 

Link with -lm.

DESCRIPTION

The acosh() function calculates the inverse hyperbolic cosine of x; that is the value whose hyperbolic cosine is x. If x is less than 1.0, acosh() returns not-a-number (NaN) and errno is set.

ERRORS

EDOM	x is out of range.

CONFORMING TO

SVr4, POSIX.1-2001, 4.3BSD, C89. The float and long double variants are C99 requirements.

SEE ALSO

asinh(3), atanh(3), cacosh(3), cosh(3), sinh(3), tanh(3)

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ACOSH (3)

2002-07-25

Generated by OpenAsthra.com from man3/acosh.3 using man macros.