# sin in R: How to Use sin() Function in R

In mathematics, the sine is a trigonometric function of an angle. For example, the sine of an acute angle is defined in the context of a right triangle. For the specified angle, it is the ratio of the length of the side opposite that angle to the length of the longest side of the triangle.

## sin in R

The sin() is a built-in mathematical R function that computes the sine value of the input numeric value. The sin() method accepts a numeric value as an argument and returns the sine value.

To calculate the sine of a value in R programming, use the sin() function.

### Syntax

``sin(x)``

### Parameters

The sin() function accepts x as a parameter.

### Example

``````a1 <- -120
a2 <- 90

sin(a1)
sin(a2)``````

#### Output

`````` -0.5806112
 0.8939967``````

## Passing pi to the sin() function

The pi is an inbuilt R constant. Let’s pass the pi to the sin() function and see the output.

``````a1 <- pi / 2
a2 <- -pi / 3

sin(a1)
sin(a2)``````

#### Output

`````` 1
 -0.8660254``````

## Applying sin() function to a Vector

To define a vector in R, use the c() function. Pass this newly created vector to the sin() function.

``````rv <- c(pi / 2, - pi / 2, pi, pi / 3)
sin(rv)``````

#### Output

`` 1.000000e+00 -1.000000e+00 1.224647e-16 8.660254e-01``

That is it for the sin() function in the R language.