# How can I evaluate a Julia function with sin/cos as real value?

**URL:** <https://discourse.julialang.org/t/how-can-i-evaluate-a-julia-function-with-sin-cos-as-real-value/24988>\
**Category:** General Usage\
**Created:** [June 6, 2019, 12:33am UTC](https://discourse.julialang.org/t/how-can-i-evaluate-a-julia-function-with-sin-cos-as-real-value/24988 "2019-06-06T00:33:26Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Nha\_Dinh\_Cao](https://avatars.discourse-cdn.com/v4/letter/n/48db29/32.png) [@Nha\_Dinh\_Cao](https://discourse.julialang.org/u/Nha_Dinh_Cao)\
**Post date:** [June 6, 2019, 12:33am UTC](https://discourse.julialang.org/t/how-can-i-evaluate-a-julia-function-with-sin-cos-as-real-value/24988/1 "2019-06-06T00:33:26Z")

</div>

Hi everyone, I have a Julia function like f(x) = x + sin(x), and then I try to type f(2), which returns 2 + sin(2). I think it is great, but is there anything to make it returns a single real number?

Thank you. It would be great if someone can help.

---

<div class="post-metadata">

**Author:** ![JeffreySarnoff](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jeffreysarnoff/32/1980_2.png) [@JeffreySarnoff](https://discourse.julialang.org/u/JeffreySarnoff)\
**Post date:** [June 6, 2019, 12:39am UTC](https://discourse.julialang.org/t/how-can-i-evaluate-a-julia-function-with-sin-cos-as-real-value/24988/2 "2019-06-06T00:39:16Z")

</div>

That does not make sense to me.

```julia
julia> f(x) = x + sin(x)
f (generic function with 1 method)

julia> f(2)
2.909297426825682

```

What exactly is your function `f`? How is it defined?