ACOS (Transact-SQL)
SQL Server 2005
A mathematical function that returns the angle, in radians, whose cosine is the specified float expression; also called arccosine.
Transact-SQL Syntax Conventions
The following example returns the ACOS of the specified angle.
SET NOCOUNT OFF; DECLARE @angle float; SET @angle = -1.0; SELECT 'The ACOS of the angle is: ' + CONVERT(varchar, ACOS(@angle));
Here is the result set.
--------------------------------- The ACOS of the angle is: 3.14159 (1 row(s) affected)
Reference
Mathematical Functions (Transact-SQL)Functions (Transact-SQL)