Complex number fundamentals | Lockdown math ep. 3

From 3Blue1Brown.

Intro to the geometry complex numbers.
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Beautiful pictorial summary by @ThuyNganVu:

– On the first sketch of a complex plane, there is a "2i" written instead of "-2i".
– At the end, in writing the angle sum identity, the last term should be sin(beta) instead of sin(alpha).
– At 1:11:37, the terms in parentheses should include an i, (1/2 + sqrt(3)/2 i)

The live question setup with stats on-screen is powered by Itempool.

The graphing calculator used here is Desmos.

The "Complex slide rule" came from Geogebra, via Ben Sparks.

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Music by Vincent Rubinetti.
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