acos-transact-sql.md

title	ACOS (Transact-SQL) | Microsoft Docs
ms.custom
ms.date	07/24/2017
ms.prod	sql
ms.prod_service	database-engine, sql-database, sql-data-warehouse, pdw
ms.reviewer
ms.technology	t-sql
ms.topic	language-reference
f1_keywords	ACOS ACOS_TSQL
dev_langs	TSQL
helpviewer_keywords	cosine ACOS function arccosine
ms.assetid	4ec6b46e-9438-4f0f-8b96-461edd84280a
author	MashaMSFT
ms.author	mathoma
manager	craigg
monikerRange	>=aps-pdw-2016||=azuresqldb-current||=azure-sqldw-latest||>=sql-server-2016||=sqlallproducts-allversions||>=sql-server-linux-2017||=azuresqldb-mi-current

ACOS (Transact-SQL)

[!INCLUDEtsql-appliesto-ss2008-all-md]

A function that returns the angle, in radians, whose cosine is the specified float expression. This is also called arccosine.

Transact-SQL Syntax Conventions

Syntax

ACOS ( float_expression )  

Arguments

float_expression
An expression of either type float or of a type that can implicitly convert to float. Only a value ranging from -1.00 to 1.00 is valid. Values outside this range return NULL, and ASIN will report a domain error.

Return Types

float

Examples

This example returns the ACOS value of the specified number.

SET NOCOUNT OFF;  
DECLARE @cos float;  
SET @cos = -1.0;  
SELECT 'The ACOS of the number is: ' + CONVERT(varchar, ACOS(@cos));  

[!INCLUDEssResult]

---------------------------------   
The ACOS of the number is: 3.14159   
  
(1 row(s) affected)  

See also

Mathematical Functions (Transact-SQL)
Functions