acos
acos
(PHP 4, PHP 5, PHP 7)
acos — Arc cosine
Description
float acos ( float $arg )
Returns the arc cosine of arg in radians. acos() is the complementary 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://secure.php.net/manual/en/function.acos.php
