I have this commutative diagram to draw :
I have no idea how to get the inner diagram to properly display and not mess with the whole thing. I can get the outer one but as soon as I do anything to try and add the extra arrow and all, I get plenty of errors, and the diagram looks nothing like the picture above (done in geogebra). I'd be grateful if anyone could help out ! Also, I have a less important issue, but is it possible to scale the diagram ? The command \begin{tikzcd}[scale=2]
doesn't seem to do anything, and the environnement \scalebox{2}{...}
produces errors and doesn't scale anything either.
Thanks.