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5 votes
0 answers
131 views

Infinite product of areas in a square, inscribed quarter-circle and line segments.

The diagram shows a square of area $An$ and an enclosed quarter-circle. Line segments are drawn from the bottom-left vertex to points that are equally spaced along the quarter-circle. The regions ...
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3 votes
0 answers
121 views

Special property of circle with radius 0.975399...

$4n$ points are uniformly distributed on a circle. Parabolas are drawn in the manner shown below with example $n=4$. The parabolas' vertices are at the center of the circle. The parabolas have a ...
Dan's user avatar
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6 votes
2 answers
270 views

What is a closed form of this limit? (product of areas in circle with parabolas)

I am looking for a closed form of $L=\lim\limits_{n\to\infty}\prod\limits_{k=1}^n \left(\left(6+\frac{4n}{\pi}\left(\sin{\frac{\pi}{2n}}\right)\left(\cos{\frac{(2k-1)\pi}{2n}}\right)\right)^2-\left(\...
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16 votes
1 answer
453 views

Closed form for $\lim\limits_{n\to\infty}\prod\limits_{k=1}^n{\left(2-\frac{2n^2-\pi^2+8}{n^2}\cos{\frac{(2k-1)\pi}{n}}\right)}$?

I am looking for a closed form for: $$\lim_{n\to\infty}\prod_{k=1}^n{\left(2-\frac{2n^2-\pi^2+8}{n^2}\cos{\frac{(2k-1)\pi}{n}}\right)}$$ (Wolfram suggests that it's approximately 6.17966.) Context: I ...
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