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cosh(3)                  Library Functions Manual                 cosh(3)
       cosh, coshf, coshl - hyperbolic cosine function
       Math library (libm, -lm)
       #include <math.h>
       double cosh(double x);
       float coshf(float x);
       long double coshl(long double x);
   Feature Test Macro Requirements for glibc (see
   feature_test_macros(7)):
       coshf(), coshl():
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
       These functions return the hyperbolic cosine of x, which is
       defined mathematically as:
           cosh(x) = (exp(x) + exp(-x)) / 2
       On success, these functions return the hyperbolic cosine of x.
       If x is a NaN, a NaN is returned.
       If x is +0 or -0, 1 is returned.
       If x is positive infinity or negative infinity, positive infinity
       is returned.
       If the result overflows, a range error occurs, and the functions
       return +HUGE_VAL, +HUGE_VALF, or +HUGE_VALL, respectively.
       See math_error(7) for information on how to determine whether an
       error has occurred when calling these functions.
       The following errors can occur:
       Range error: result overflow
              errno is set to ERANGE.  An overflow floating-point
              exception (FE_OVERFLOW) is raised.
       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ cosh(), coshf(), coshl()             │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘
       C11, POSIX.1-2008.
       C99, POSIX.1-2001.
       The variant returning double also conforms to SVr4, 4.3BSD.
       In glibc 2.3.4 and earlier, an overflow floating-point
       (FE_OVERFLOW) exception is not raised when an overflow occurs.
       acosh(3), asinh(3), atanh(3), ccos(3), sinh(3), tanh(3)
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Linux man-pages 6.15            2025-05-17                        cosh(3)
Pages that refer to this page: acosh(3), asinh(3), atanh(3), sinh(3), tanh(3)