Ellipse perimeter
Ellipse perimeter: use first semiaxis, second semiaxis. Review the formula, worked example and calculation steps.
Inputs
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Formula & explanation
Ramanujan: P ≈ π(a+b)[1+3h/(10+√(4−3h))], h=((a−b)/(a+b))²
Variables & units
- First semiaxis
- m · minimum 0.000001, maximum 1000000000000
- Second semiaxis
- m · minimum 0.000001, maximum 1000000000000
Worked example
A circle with both semiaxes 1 m gives 2π m.
Assumptions
A high-accuracy approximation for ellipses, not an exact elementary formula.
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Practice with an example
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