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Came across this on the internet. I have some ideas regarding this but I wanted to know more such reasonings.
Proof of Pi


marked as duplicate by Lord Shark the Unknown, Namaste, Matthew Conroy, Henry, gt6989b May 4 '17 at 17:16

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  • $\begingroup$ Came across what? $\endgroup$ – Lord Shark the Unknown May 4 '17 at 17:08
  • $\begingroup$ Sorry missed the picture earlier. Edited it now. $\endgroup$ – Diyanko Bhowmik May 4 '17 at 17:09
  • $\begingroup$ Vi Hart had a video on Pi being equal to 4. You should watch it. $\endgroup$ – Chickenmancer May 4 '17 at 17:10
  • 4
    $\begingroup$ The step "repeat to infinity" should immediately make you suspicious. I've heard someone is still trying to catch a tortoise with that one. $\endgroup$ – Clement C. May 4 '17 at 17:11
  • $\begingroup$ Duplicate $\endgroup$ – Namaste May 4 '17 at 17:12

Fundamentally, you have jumped in without a definition of the length of an arc.

The circumference isn't approximated by the sum of lengths of the lines drawn as shown in the image, but by the sum of the hypotenuses of the right-angled triangles formed around the edge of the circle.


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