9.23.3 Can you answer these questions?

9.23.3.1 Problems when solving a system of PDEs with NDSolve

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=287136

I am currently attempting to solve the following exercise question using NDSolve directly (ref.: Davis, M. E. (2013). Numerical methods and modeling for chemical engineers. Courier Corporation.). 
... 
[differential-equations] [system]
 

asked by Al Mossar https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=93408 Score of 1

9.23.3.2 Can the segmented function display its Domain of a function completely?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=287311

 In[10]:= Floor[x Floor[x]] // PiecewiseExpand[#, 0 <= x <= 4, Reals] & 
 
 
Can 'true' be automatically generated as the corresponding x range: 0<=x<1 
[functions]
                                                                                  

                                                                                  
 

asked by csn899 https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=68574 Score of 1

9.23.3.3 Chat block divider in a Chat-Enabled Notebook using Swedish keyboard

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=287132

(I'm using Mathematica 13.3.0 on a Linux Ubuntu 20.04.6 LTS, using a Swedish keyboard.) 
In a Chat-Enabled Notebook, the "~" (the tilde character) is used to create a Chat block divider/... 
[notebooks] [llmfunction]
 

asked by hakank https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=4935 Score of 1