Monday, October 19, 2020

Homework for discussion-Eye of Horus



I saw this symbol before, but I didn't know the associated myth. It is interesting to read. The most fascinating parts I found in my research are the way of ancient Egyptians using unit fraction for dividing their grain  and also the calculation method they used,for example:

For small odd prime denominators p, the expansion 2/p = 2/(p + 1) + 2/p(p + 1) was used

For the small composite denominators, they do the following

expansion 2/pq as 1/pr + 1/qr, where r = (p+q)/2.

I tried an example 2/33, so based on the method above, we have 

33=3x11, let p=3,q=11, and then r=(3+11)/2=7

so, 2/33= 1/(3x7) +1/(11x7)

comparing to the modern method, the Egyptian method has more work to do.

I also found it is interesting that when associate the Eye of Horus with dividing the square, It is easy to see the sum of  A =  B = 1




A=
B=


In ancient China, Nine" and "five" symbolize the authority of the emperor, and they are called "Nine-Five Supreme." Numbers were divided into yang and yin, with odd numbers as yang and even numbers as yin. Nine is the highest in the yang number, and five is in the middle. Therefore, "nine" and "five" are used to symbolize the emperor's authority, which is called "nine-five supreme." As the emperor of the "Nine-Five Supreme," the emperor is inseparable from the "Nine." He wears a Nine Dragon Robe. What's more interesting is that even the palace buildings are related to "Nine." For example, Beijing City has nine gates, Tiananmen Square has nine wide floors, and the gates are decorated with nine nails (that is, each door has nine rows of nails vertically and horizontally).  These are all symbols of longevity. Of course, the worship of the "Nine" in the Temple of Heaven and the Forbidden City may have a deeper meaning.

https://zhidao.baidu.com/question/99367925.html

1 comment:

  1. Megan, this is a lovely discussion of mathematical thinking and practices from your research. Thank you for sharing ancient China number knowledge. I would love to know more.

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