acosh
(PHP 4 >= 4.0.7, PHP 5)
acosh — Inverse hyperbolic cosine
說明
float acosh
( float $arg
)
Returns the inverse hyperbolic cosine of arg , i.e. the value whose hyperbolic cosine is arg .
Note: 本函式未在 Windows 平台下實作。
參數
- arg
-
The value to process
Return值
The inverse hyperbolic cosine of arg