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Function cos #
Calculate the cosine of a value.
For matrices, the function is evaluated element wise.
Syntax #
```js
math.cos(x)
```
Parameters #
Parameter | Type | Description
--------- | ---- | -----------
`x` | number | BigNumber | Complex | Unit | Array | Matrix | Function input
Returns #
Type | Description
---- | -----------
number | BigNumber | Complex | Array | Matrix | Cosine of x
Examples #
```js
math.cos(2) // returns number -0.4161468365471422
math.cos(math.pi / 4) // returns number 0.7071067811865475
math.cos(math.unit(180, 'deg')) // returns number -1
math.cos(math.unit(60, 'deg')) // returns number 0.5
const angle = 0.2
math.pow(math.sin(angle), 2) + math.pow(math.cos(angle), 2) // returns number ~1
```
See also #
[cos](cos.html),
[tan](tan.html)