Php/docs/function.acos
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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.
