# cos {#cos}

**Parent topic:**[Functions](../../Functions/category.md)

## Syntax {#syntax}

`cos(X)`

## Arguments {#arguments}

**X** is a scalar/vector/matrix.

## Details {#details}

Apply the function of cos to X.

## Examples {#examples}

```
cos 0 1 2;
// output: [1,0.540302,-0.416147]
```

Related functions: [asin](../a/asin.md), [acos](../a/acos.md), [atan](../a/atan.md), [sin](../s/sin.md), [tan](../t/tan.md), [asinh](../a/asinh.md), [acosh](../a/acosh.md), [atanh](../a/atanh.md), [sinh](../s/sinh.md), [cosh](cosh.md), [tanh](../t/tanh.md)

