12.2.3 Can you answer these questions?

12.2.3.1 What does DirectedInfinity[0] mean?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318406

I calculated the Limit of an large expression by assuming that the symbolic quantities a, b occuring in the expression are real. I get the following result: 
... 
[calculus-and-analysis] [functions]
 

asked by kbeku beku https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=105814 Score of 1

12.2.3.2 How to constraint solutions to FindRoot to avoid trivial solutions

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318395

I have a pretty long function that has trivial solutions near x = 0, and other solutions somewhere near 0, around 0.1. 
To simplify things, the function looks like 
... 
[equation-solving] [constraint]
                                                                                  

                                                                                  
 

asked by Ee Kin Chan https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=101801 Score of 1

12.2.3.3 How to draw a full-width separator line below "Section" cells including over the cell bracket area?

https://mathematica.stackexchange.com/landing/r/digest?cta=question&id=318413

In my custom stylesheet for technical reports, I would like to add a thin horizontal separator line below every "Section" cell that spans the entire width of the notebook page, including the ... 
[formatting] [cells] [stylesheet]
 

asked by Flint https://mathematica.stackexchange.com/landing/r/digest?cta=user&id=115347 Score of 1