and and are the semi axes of the elipse.
Note that the circumference is given by an infinite sum (series) and therefore cannot be calculated exactly. But taking a large number N of terms in the series, will ensure that the circumference is obtained with a good accuracy. You have the possibility of changing N in the calculator below and see how C converges towards a "fixed value" as you increase N.
How to use the calculator
Enter the semi axes (0 or greater) and (0 or greater) and N (integer, 1 or greater) the number of terms in the series and press "calculate".
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