Pentagons and the Golden Ratio - Numberphile

Continuing on from Zvezda’s previous video about Ptolemey’s Theorem (see: https://youtu.be/bJOuzqu3MUQ) now we use it to prove some cool stuff with pentagons and equilateral triangles.
More links & stuff in full description below ↓↓↓

Zvezda’s Numberphile playlist: http://bit.ly/zvezda_videos

Zvezda’s webpage: https://math.berkeley.edu/~stankova/

Golden Ratio: https://youtu.be/sj8Sg8qnjOg

Epic Circles: https://youtu.be/sG_6nlMZ8f4

Triangle Magic Highway: https://youtu.be/wVH4MS6v23U

Numberphile is supported by the Mathematical Sciences Research Institute (MSRI): http://bit.ly/MSRINumberphile

We are also supported by Science Sandbox, a Simons Foundation initiative dedicated to engaging everyone with the process of science. https://www.simonsfoundation.org/outreach/science-sandbox/

And support from Math For America – https://www.mathforamerica.org/

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