I am trying to add a noise term in my formula, but I do not know how to make it happen.

For example, I have a function:

```
function_1 <- function(var1, var2, var3) {
output <- (2*var1) + (-1*var2) + (3*var3)
return(output)
}
```

But, I want to add a noise term in my formula like the following:

```
function_2 <- function(var1, var2, var3) {
output <- (2*var1) + (-1*var2) + (3*var3) + noise
return(output)
}
```

How could I make "function_2" in R properly? If any of you have any idea? I wanted to use the jitter function, but I am not sure if this may work or not.

```
function_2 <- function(var1, var2, var3) {
output <- jitter((2*var1) + (-1*var2) + (3*var3))
return(output)
}
```

Please let me know what do you guys think.