I'm trying to use sage for documentation purposes, and I'm looking for a way to do some of the following.

Enter an equation
`f(x) = 2x`

Input `f(2)`

or something close
and get back `f(2) = 4`

instead of just 4.

I'm also looking for a way to input
`f(x) = 2x^2`

Input diff(f(x),x), or an equivalent command and get
`f'(x) = 4x`

or `d(f(x)/dx = 4x`

.

And an icing on the cake would being able to input `integrate(f(x)dx)`

and return `∫f(x)dx => 4x + 15 + c`

Bassically, if there is a way to the output more verbose, I'd love to know how.

I just started using Sage and I love it, thank you!

**Edit:**
Thank you so much for the response ~~@paulmasson~~

@paulmasson
Your word "typesetting" was new to me and helped me find some other posts.

~~This ~~This seems to be my exact ~~question:
https://ask.sagemath.org/question/7826/latex-typesetting-for-derivatives-like-g~~

This question:

This one seemed to answer my question, but I don't know if I'm supposed to do ~~this.
https://ask.sagemath.org/question/30975/present-sage-output-as-normal-mathematics/~~this.

It gave me the idea of using `f = function('f',x) == 2*x`

I have no clue what `function()`

is, but I'm working on it.

I have no idea how or why this is different from `f(x) = 2*x`

, but it's pretty cool because now `diff(f,x)`

evaulates to `d(f(x)/dy = 2`

However, it doesn't do `diff(f)`

so well when there are two variables like `f(x,y) = x^2 + y^2`

.

I also really enjoyed this ~~one:
https://ask.sagemath.org/question/24039/showing-both-input-and-output/~~one:

*Edit:* Links, and I'm sorry to the moderator that has to keep approving my edits. Thank you for your time. I promise this will be my last edit.