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Topic: Blankenhorn-Ramanujan Ellipse circumference formula
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Posts: 37
Registered: 12/23/11
Blankenhorn-Ramanujan Ellipse circumference formula
Posted: Dec 25, 2012 7:35 PM
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Added improvement to the Blankenhorn-Ramanujan ellipse circumference formula with easier to memorize numbers:

C~pi(a+b)*(1+3h/(10+sqrt(4-3h)) +(1.5*h^6-0.5*h^12)/((11pi/(44-14pi))+24100(1-h)))

Where a and b are the half length axes and h = (a-b)^2/(a+b)^2

Referencing, replace the h^5.20114 with 1.5*h^6-0.5*h^12, and the 19176 with 24100.


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