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ellipse described about the circle in which a regular pentagon is constructed mapped on an ellipseenter image description here

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The surface can be calculated from my formula

$A=\frac{a.b.\pi.\alpha}{360}$

Total area will be an ellipse

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Area n work will be

$An=\frac{b.\sin\alpha.a \cos\alpha}{2}+\frac{b.\sin\alpha.a(1-\cos\alpha)}{2} $

$An=\frac{a.b}{2}(\sin\alpha\cos\alpha+\sin\alpha-\sin\alpha\cos\alpha) $

$An=\frac{a.b}{2}\sin\alpha=\frac{a.b}{2}\sin(\frac{360}{n}) $

How is this n part of it multiplied by n

$ A=a.b.\pi $

$ \frac{n}{2}\sin(\frac{360}{n})$ look

3 Answers 3