The simpler quadratic formula | Lockdown math ep. 1
3Blue1Brown 3Blue1Brown
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 Published On Apr 17, 2020

Another view on the quadratic formula.
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Beautiful pictorial summary by @ThuyNganVu:

Po Shen Loh on quadratics:

Welch Labs on imaginary numbers:

Mistakes (there will always be mistakes):
At minute 22, I write "b' / 2" instead of "-b' / 2".

0:00 - Introduction
2:56 - "How often am I going to use this?" + ray tracing example
5:38 - Mental math tricks (factoring numbers, differences of squares)
13:36 - Properties of quadratic functions
18:40 - Deriving the variant quadratic formula
23:07 - Practice problems (ft. complex numbers!)
34:10 - Deriving the traditional quadratic formula from the variant
41:07 - Conclusion (key takeaways)
43:21 - Fun with joke poll questions

Music by Vincent Rubinetti.
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