Outline:

Answers that can be useful

• From me
• From other users
• Just for fun

Answers that can be useful for more generic problems:

From me

• Finding roots of a parametric non linear system :

https://mathematica.stackexchange.com/a/277272/86543 and https://mathematica.stackexchange.com/a/271973/86543

• Prevent automatic conversion of a*a to a^2 :

https://mathematica.stackexchange.com/a/273784/86543

• Tensor algebra and analysis in Mathematica:

https://mathematica.stackexchange.com/a/274277/86543

https://mathematica.stackexchange.com/a/274371/86543

• Wolfram Engine with Jupyter or VScode

https://mathematica.stackexchange.com/a/274441/86543

• Neural network map operator with GPU (only the first part):

https://mathematica.stackexchange.com/a/274980/86543

• Symbolic calculations with predefined symbols

https://mathematica.stackexchange.com/a/275265/86543

• Define functions from global variables:

https://mathematica.stackexchange.com/q/275481/86543

• Equivalent of Thinning for a graphics object:

https://mathematica.stackexchange.com/a/276405/86543

• Simplifying sums of products:

https://mathematica.stackexchange.com/a/276476/86543

• Dark mode notebook:

https://mathematica.stackexchange.com/a/276560/86543

• Writing asymptotic expressions with divergent terms:

https://mathematica.stackexchange.com/a/277141/86543

• Convert expression to hyper geometric form:

https://mathematica.stackexchange.com/a/277396/86543

• Series from a differential equation

https://mathematica.stackexchange.com/a/277427/86543

• Any polynomial root as the solution to a differential equation:

https://mathematica.stackexchange.com/a/277527/86543

• Simplify can depend on variable names:

https://mathematica.stackexchange.com/a/277635/86543

• Integrals with integer parameters:

https://mathematica.stackexchange.com/a/277989/86543

Other users :

• Nothing for patterns :

https://mathematica.stackexchange.com/a/273543/86543

• Simplifying with Sum :

https://mathematica.stackexchange.com/a/273795/86543

• permutation that relates two expressions:

https://mathematica.stackexchange.com/q/274201/86543

• Region delimited by lines

https://mathematica.stackexchange.com/a/276824/86543

• Autocomplete with Resource functions:

https://mathematica.stackexchange.com/a/276346/86543

• Extract surface from a 3D plot

https://mathematica.stackexchange.com/q/276903/86543

Just for fun

• Sorting symbols by complexity

https://mathematica.stackexchange.com/a/274817/86543

• Making a simple pipe network

https://mathematica.stackexchange.com/a/276719/86543

• Different ways to express the number 2023

https://mathematica.stackexchange.com/a/278028/86543