Improved and corrected LaTeX printing of Mod

[oscargus]

References to other Issues or PRs

Brief description of what is fixed or changed

Earlier Mod(x, y + 1) was printed as

Now it is printed as

Also, the LaTeX used \bmod{7} which is incorrect. It should just be \bmod 7 as \bmod is not a command. (Probably a confusion with \pmod which is used like that.)

Other comments

Still an issue with unary -, where both -Mod(x, y) and Mod(-x, y) ends up with the same output.

Release Notes

• printing
  • Improved and corrected LaTeX-printing of Mod.

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• printing
  • Improved and corrected LaTeX-printing of Mod. (#22091 by @oscargus)

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#### Brief description of what is fixed or changed
Earlier `Mod(x, y + 1)` was printed as
![image](https://user-images.githubusercontent.com/8114497/133048450-177d27fe-8720-45e9-b9a6-c39831e4f412.png)

Now it is printed as
![image](https://user-images.githubusercontent.com/8114497/133048044-d0e232b3-a1b2-48ad-b7ac-8c840f9be838.png)

Also, the LaTeX used `\bmod{7}` which is incorrect. It should just be `\bmod 7` as `\bmod` is not a command. (Probably a confusion with `\pmod` which is used like that.)

#### Other comments
Still an issue with unary -, where both `-Mod(x, y)` and `Mod(-x, y)` ends up with the same output.

#### Release Notes

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* solvers
  * Added a new solver for logarithmic equations.

* functions
  * Fixed a bug with log of integers.

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<!-- BEGIN RELEASE NOTES -->
* printing
     * Improved and corrected LaTeX-printing of `Mod`. 
<!-- END RELEASE NOTES -->

Update

The release notes on the wiki have been updated.

[smichr]

+1

[oscarbenjamin]

Thanks