asin - chung-leong/qb GitHub Wiki
asin - Arc sine
float asin ( float $x )
Returns the arc sine of x 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:
x - The argument to process. It can be a scalar or an array.
Return Value:
The arc sine of x in radians. If x is an array, the return value will also be an array.
Version
1.0 and above.