Yay basic inequalities

[sniffnoy]

AM-GM is surprisingly useful in dealing with SL₂(R).

Comments

[sniffnoy.livejournal.com]

From last week's homework: What are the conjugacy classes of SL₂(R)? Which ones are closed? Which one contain the identity in their closure?

From these week's homework: Show that all finite subgroups of SL₂(R) are cyclic.

Used it in both of them. And other similar inequalities.

[sniffnoy.livejournal.com]

No, that doesn't work at all. For instance there's no way you could put [-1/2 √3/2 ; -√3/2 -1/2] in that form.