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Groups > geometry.research > #8
| From | Anyssa <remany.anissa@yandex.com> |
|---|---|
| Newsgroups | geometry.research |
| Subject | Re: The value of 'Pi' |
| Date | 2017-08-21 14:56 +0000 |
| Organization | The Math Forum |
| Message-ID | <156432308.39708.1503327315319.JavaMail.root@sodium.mathforum.org> (permalink) |
> THE VALUE OF Pi > Author: Shyamal Kumar Das (User ID: 642576) > E-mail ID: das.shyamal1c@gmail.com > TO: All Mathematicians > > On the Pi Day, I would like to state that I have > calculated out the value of Pi in a different way. > In doing so, I have taken the help of my previous > deduction which reveals that when the angle subtended > at the center tends to zero, the difference between > the arc length and the chord length tends to zero. > The proof of the above statement is as follows: > Proof: Let us consider an angle of 4.5 degree > arbitrarily. > Here, the angle subtended at the center =4.5 degree > e = Pi/40 radian. > The difference between arc length and chord length = > Pi/40 × R - 2 R × sin 2.25 = R (0.07854 -2× > 2× 0.03926) = R ( 0.07854 - 0.07852) = > 0.00002 R, which means 2/ 100000 parts of unit > it radius. > Hence, it is revealed that when angle subtended at > t the center by an arc is 4.5 degree, the chord > length is almost equal to the arc length. If we > take 2.25 deg. or 1.125 deg. the difference will be > lesser and least. > > Now, with the help of the above deduction, I am going > to find out the value of Pi. > > Calculation: Let us consider a circle of unit radius > and we will take half of it, i.e., > semi-circle which subtends an angle of 180 deg. at > the center. Now, we will bisect the given angle 8 > times, to get a sector which is 1 / 256 part of the > semi-circle and which subtends an angle of 180 / 256 > or 45 / 64 deg. at the center. > If we join the two end points of the base of this > is sector, we will get an isosceles triangle. Hence, > the given semi-circle consists of 256 nos. of sectors > and so 256 nos. of isosceles triangles, considering, > the arc length and chord length same. > The length of each base of these 256 triangles = 2 > 2 sin (45 / 128) > Hence, total length of bases of 256 triangles > = The semi-circumference of the circle of unit > nit radius > Since, Pi is equal to semi-circumference of a circle > of unit radius, > Pi = 256 × 2 sin 45/128 deg. = 512 sin 180/512 > 80/512 deg. > > Again, area of semi-circle = area of one isosceles > triangle × 256 > = 1/2 × [2 sin ( 45 / 128) × cos ( 45 / 128)] > / 128)] × 256 > = 1/2 × sin (45/ 64) × 256 > So, area of the circle = 2× 1/2 sin (45/ 64) × 256 > = sin (45/ 64) × 256 = 256 sin (180 > = 256 sin (180 / 256) > Since, Pi is equal to area of a circle of unit > nit radius, > Pi = 256 sin (180 / 256) > The above calculation is made taking 8 times > bisections of a circle, which means 256 equal parts > of the semi-circle and/or 512 equal parts of the > whole circle. > If we take 9 times bisections of the circle, which > means 512 equal parts of the semi-circle and/or 1024 > equal parts of the whole circle, > Pi = 1024 sin 180/1024 deg. or 512 sin 180/512 deg. > (Here, 2 to the power 9 = 512) > >From the above, we can derive a new formula of Pi, > which is as below: > The value of Pi = X sin 180/X deg., where X = No. of > equal parts of the circle . > Here, please note, for bigger circle, no. of > bisections will be more. So, X depends on the > magnitude of the radius of the given circle. I better understand now. Pi is a very interesting value.
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Re: The value of 'Pi' Anyssa <remany.anissa@yandex.com> - 2017-08-21 14:56 +0000
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