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Topic: Unusual dynamic applet demonstrates multiplication via a circle...
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Jonathan Crabtree

Posts: 351
Registered: 12/19/10
Unusual dynamic applet demonstrates multiplication via a circle...
Posted: Feb 21, 2015 10:18 AM
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Dear friends

I stumbled across the idea of depicting multiplication via a circle with only a unit, and two distinct factors in a Latin book published in 1615.

The result is a dynamic applet at http://www.jonathancrabtree.com/mathematics/multiplication-circles/

Have you seen this before or come across a formal proof why it works?

Please let me know!

Best wishes
Jonathan Crabtree
Mathematics Researcher
The Evolution of Elementary Mathematics
http://www.j.mp/jcrabtree (LinkedIn)
http://www.jonathancrabtree.com/mathematics



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