Trigonometry fundamentals | Lockdown math ep. 2


From 3Blue1Brown.

Intro to trig with a lurking mystery about cos(x)^2
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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) & cos(3)  – 16:44
SohCahToa – 20:44
Q5 Leaning Tower  – 22:29
How to Compute Trig Functions?  – 30:59
Q6 sin(π/6)  – 33:34
Q7 cos(π/6)  – 36:19
Q8 Trig of -θ  – 43:34
Computing Trig Functions  – 47:44
Q9 cos(π/12)  – 0:49:54
Adv Trig Functions  – 0:56:44
Q10 Graph of tan(θ)  – 1:00:30
JSON comment  – 1:02:24
“The most exciting part of the lecture” –1:05:34


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Music by Vincent Rubinetti.
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