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title: "TAN (Transact-SQL) | Microsoft Docs"
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---
# TAN (Transact-SQL)
[!INCLUDE[tsql-appliesto-ss2008-all-md](../../includes/tsql-appliesto-ss2008-all-md.md)]

  Returns the tangent of the input expression.  
  
 ![Topic link icon](../../database-engine/configure-windows/media/topic-link.gif "Topic link icon") [Transact-SQL Syntax Conventions](../../t-sql/language-elements/transact-sql-syntax-conventions-transact-sql.md)  
  
## Syntax  
  
```  
TAN ( float_expression )  
```  
  
## Arguments  
 *float_expression*  
 Is an [expression](../../t-sql/language-elements/expressions-transact-sql.md) of type **float** or of a type that can be implicitly converted to **float**, interpreted as number of radians.  
  
## Return Types  
 **float**  
  
## Examples  
 The following example returns the tangent of `PI()/2`.  
  
```  
SELECT TAN(PI()/2);  
```  
  
 [!INCLUDE[ssResult](../../includes/ssresult-md.md)]  
  
```  
----------------------  
1.6331778728383844E+16  
```  
  
## Examples: [!INCLUDE[ssSDWfull](../../includes/sssdwfull-md.md)] and [!INCLUDE[ssPDW](../../includes/sspdw-md.md)]  
 The following example returns the tangent of .45.  
  
```  
SELECT TAN(.45);  
```  
  
 [!INCLUDE[ssResult](../../includes/ssresult-md.md)]  
  
 ```
--------  
0.48
```  
  
## See Also  
 [Mathematical Functions (Transact-SQL)](../../t-sql/functions/mathematical-functions-transact-sql.md)