asin
(PHP 4, PHP 5)
asin — Arc sine
Description
float asin
( float $arg
)
Returns the arc sine of arg in radians. asin() is the complementary 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