SQL Server/T-SQL/Math Functions/ACOS

ACOS: Returns as a float data type, the angle in radians to the entered cosine

1> -- ACOS: Returns as a float data type, the angle in radians to the entered cosine,
2> -- which must have values between -1 and 1.
3>
4> -- This function is the inverse of COS.
5>
6> SELECT ACOS(0.33)
7> GO
------------------------
      1.2344927516409163
(1 rows affected)
1>