Php/docs/function.asin
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asin
(PHP 4, PHP 5, PHP 7)
asin — Arc sine
Description
asin
( float $arg
) : float
Returns the arc sine of arg in radians.
asin() is the inverse function of
sin(), which means that
a==sin(asin(a)) for every value of a that is within
asin()'s range.
Parameters
arg- The argument to process
Return Values
The arc sine of arg in radians
