4.34.2 Greatest hits from previous weeks

4.34.2.1 Is it possible to draw this figure using Mathematica?

https://mathematica.stackexchange.com/questions/110848/is-it-possible-to-draw-this-figure-using-mathematica

 
The figure is 
 
 
 
See the how-to video or a speeded-up GIF. 
 
I believe it should be possible to draw this figure programmatically using some Random function, but I'm rather new to Mathematica, so I  ...
 

- asked by AccidentalFourierTransform (62 votes), answered by M.R. (86 votes)

4.34.2.2 Can Mathematica do symbolic linear algebra?

https://mathematica.stackexchange.com/questions/3242/can-mathematica-do-symbolic-linear-algebra

 
For instance, is there some way I can say "let A and B be arbitrary real $m\times n$ and $k\times m$ matrices, Simplify[Transpose[Transpose[A].Transpose[B]]]" and Mathematica would simplify it to B.A? 
...
 

- asked by nikie (47 votes), answered by helen (25 votes)