acos

    (PHP 4, PHP 5, PHP 7, PHP 8)

    acos — Arc cosine

    Description

    acos(float$num): float

    Returns the arc cosine of num in radians. acos() is the inverse function of cos(), which means that $num == cos(acos($num)) for every value of num that is in the domain of acos().

    Parameters

    num

    The argument to process

    Return Values

    The arc cosine of num in radians.

    See Also

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