Uploaded May 2019 | Updated September 2026, 2 weeks ago

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See more James Grime over on Singing Banana.
youtube.com/singingbanana

He is also on some channel called Numberphile.
bit.ly/grimevideos

We have some teacher notes and activity resources for this video on Think Maths. See if your students can find a better graphical proof for the case of 4k than we did! Spoiler: there is one.
think-maths.co.uk/standupmaths-videos#two-squares


CORRECTIONS
- Nothing yet. Let me know if you spot anything!

Thanks to my Patreon supports who do support these videos and make them possible. Here is a random subset:

Daniel Brahneborg
Jan Strohbeck
Marcel de Jong
Thomas Kristian Hodnemyr
Linus Törnqvist

Support my channel and I can make more maths videos:
patreon.com/standupmaths

Music by Howard Carter
Filming and editing by Matt Parker
Design by Simon Wright
Some maths by James Grime.

MATT PARKER: Stand-up Mathematician
Website: standupmaths.com
Maths book: wwwh.umble-pi.com
Nerdy maths toys: mathsgear.co.uk