# **COS()**

## **函数说明**

COS() 函数返回输入参数（用弧度表示）的余弦值。

## **函数语法**

```text
> COS(number)
```

## **参数释义**

|  参数   | 说明  |
|  ----  | ----  |
| number | 必要参数，可取任意数值数据类型 |

## **示例**

```text
drop table if exists t1;
create table t1(a int,b float);
insert into t1 values(1,3.14159);
insert into t1 values(-1,1.57);

mysql> select cos(a),cos(b) from t1;
+--------------------+----------------------+
| cos(a)             | cos(b)               |
+--------------------+----------------------+
| 0.5403023058681398 |  -0.9999999999967865 |
| 0.5403023058681398 | 0.000796274258662553 |
+--------------------+----------------------+
2 rows in set (0.01 sec)
```