acos
(PHP 4, PHP 5, PHP 7)
acos — Arc cosine
Description
acos ( float $arg ) : float
Returns the arc cosine of arg
in radians. acos() is the inverse function of cos(), which means that a==cos(acos(a))
for every value of a that is within acos()' range.
Parameters
-
arg
-
The argument to process
Return Values
The arc cosine of arg
in radians.
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.acos.php