Honestly when i started lv.3, i can't understand some of Brilliant solution really work. It's maybe because i do not know many theories.. I have request for physics practice in Brilliant before but it not never happens until now. By the way i wanted to ask for a new menu in Brilliant for math and physics theories(with the level include) but knowing that my first request is still not happens. I ask you "what is your another recommended site that can support solving brilliant problem of the week?" Is there any kind site like that? who groups math and physics theories to be enjoy like Brilliant problem? (not like wikipedia because we have to find keyword and before start brilliant i did'nt enjoy to solve kind of hard problem because i never find solution if the problem really hard for me.)
I know books is best resource for theories but for me it's boring to read many books beside i don't have the theories book for them. Not everyone in the world get books or good teacher to be this far so that's why i ask you for good site that almost everybody can reach.