Intro to trig with a lurking mystery about cos(x)^2
Full playlist: www.youtube.com/playlist?list=PLZHQObOWTQDP5CVelJJ1bNDouqrAhVPev
Home page: www.3blue1brown.com
Brought to you by you: 3b1b.co/ldm-thanks

— Contents:
Introduction  - 0:00
Q1 Graph of (cos θ)²  - 2:14
Q2 Translations of cos θ to (cos θ)²  - 5:34
Q3 f(2x) = f(x)²  - 10:54
Intro to Trig  - 13:14
Q4 sin(3)