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.service: "" ms.component: "t-sql|functions" ms.reviewer: "" ms.suite: "sql" ms.technology:

• "database-engine" ms.tgt_pltfrm: "" 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 caps.latest.revision: 43 author: "edmacauley" ms.author: "edmaca" manager: "craigg" ms.workload: "Inactive" monikerRange: ">= aps-pdw-2016 || = azuresqldb-current || = azure-sqldw-latest || >= sql-server-2016 || = sqlallproducts-allversions"

---

ACOS (Transact-SQL)

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

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

Transact-SQL Syntax Conventions

Syntax

ACOS ( float_expression )  

Arguments

float_expression
Is an expression of the type float or of a type that can be implicitly converted to float, with a value from -1 through 1. Values outside this range return NULL and report a domain error.

Return Types

float

Examples

The following example returns the ACOS 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)  

[!INCLUDEssSDWfull] and [!INCLUDEssPDW]

The following example returns the ACOS of the specified number.

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