The simpler quadratic formula | Lockdown math ep. 1

2020-04-17

[public] 891K views, 45.4K likes, dislikes audio only

Another view on the quadratic formula.

Full playlist: https://www.youtube.com/playlist?list=PLZHQObOWTQDP5CVelJJ1bNDouqrAhVPev

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Beautiful pictorial summary by @ThuyNganVu:

https://twitter.com/ThuyNganVu/status/1258217451323416577

Po Shen Loh on quadratics:

https://www.youtube.com/watch?v=ZBalWWHYFQc

Welch Labs on imaginary numbers:

https://www.youtube.com/playlist?list=PLiaHhY2iBX9g6KIvZ_703G3KJXapKkNaF

Mistakes (there will always be mistakes):

At minute 22, I write "b' / 2" instead of "-b' / 2".

Thanks to these viewers for their contributions to translations

Hebrew: Omer Tuchfeld

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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

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Music by Vincent Rubinetti.

Download the music on Bandcamp:

https://vincerubinetti.bandcamp.com/album/the-music-of-3blue1brown

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If you want to contribute translated subtitles or to help review those that have already been made by others and need approval, you can click the gear icon in the video and go to subtitles/cc, then "add subtitles/cc". I really appreciate those who do this, as it helps make the lessons accessible to more people.

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