/sci/ - Science & Math

1. What's the best source for useful maths at university or above level? Do you go through entire textbook sections or do you pick and choose little bits that look interesting?

I have a few preferences but i want to know if you enjoyed anything. I dont want to wallow in entry level stuff.

2. How do you get over frustration when stuck? I never know whether I'm missing something obvious or missing a hard trick.

>tfw i want to learn maths in my free time but my fragile ego can't stand being stuck on problems
>tfw it's so much easier to ignore hard things