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Subject: "Is my proof of Pythagorean Theorem valid and original?"     Previous Topic | Next Topic
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onecentrob
Member since Jun-25-10
 Jun-25-10, 10:22 AM (EST)
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"Is my proof of Pythagorean Theorem valid and original?"
 
   Following a brief correspondence with Eli Maor, he suggested I post my proposed proof of the Pythagorean Theorem to this forum:

I have attached it as a GIF file to this post.

I would be very interested to read your comments on its validity and originality.

Many thanks.

Rob

Attachments
https://www.cut-the-knot.org/htdocs/dcforum/User_files/4c24c43d2baa63bb.gif

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alexbadmin
Charter Member
2525 posts		 Jun-25-10, 10:28 AM (EST)
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1. "RE: Is my proof of Pythagorean Theorem valid and original?"
In response to message #0
 
   Do have a look at

https://www.cut-the-knot.org/pythagoras/index.shtml#8

i.e., proof #8 at the Pythagorean theorem page.


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onecentrob
Member since Jun-25-10
 Jun-29-10, 03:40 PM (EST)
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2. "RE: Is my proof of Pythagorean Theorem valid and original?"
In response to message #1
 
   Thanks for your reply Alex. Sorry for my slow response - I forgot to subscribe to the thread.

Yes, proof #8 does look rather similar. Disappointing but not surprising.

Whilst considering my last offering, another idea occurred to me. The following proof is very similar to proof #6 & #19 on the Pythagorean Page, and the "Folding Bag" proof in Eli Maor's book, but I've not seen its exact construction before. I like its simplicity:

Rob

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alexbadmin
Charter Member
2525 posts		 Jun-29-10, 03:42 PM (EST)
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3. "RE: Is my proof of Pythagorean Theorem valid and original?"
In response to message #2
 
   This time it's here:

https://www.cut-the-knot.org/pythagoras/PythagorasBySimilarity.shtml

Scroll to about the middle of the page. The argument is by Vladimir Nikolin.


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onecentrob
Member since Jun-25-10
 Jun-29-10, 04:13 PM (EST)
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4. "RE: Is my proof of Pythagorean Theorem valid and original?"
In response to message #3
 
   Thanks. Hope I've not wasted too much of your time. I did have a thorough look through the Pythagorean proof page but I clearly overlooked the link to the Pythagoras by Similarity page.

Very interesting that both this and my previous sumission were both originally proposed by Vladimir Nikolin.

Excellent site.

Rob


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alexbadmin
Charter Member
2525 posts		 Jun-29-10, 04:51 PM (EST)
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5. "RE: Is my proof of Pythagorean Theorem valid and original?"
In response to message #4
 
   Thank you.

Hitting on Vladimir's proofs is indeed a rather curious coincidence.


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