C Programming/complex.h/casinh

Description
is one of the Standard C library functions in the complex.h header file. It is used to calculate the complex and inverse hyperbolic sine of given angle or number. Just like sine operator has inverse as sin inverse, hyperbolic sine of complex number has this as an inverse function.

if casinh(x) = y, then x = csinh(y). It can be also evaluated as: casinh(x) = clog(x+csqrt(x*x+1))

return value
This function returns complex arc hyperbolic sine,in the range mathematically unbounded along real axis and in the interval $$[-i\pi/2,+i\pi/2]$$ along imaginary axis.

compatibility
Win32, C99 7.3.6.2