Calculation of Area of Annulus

Annulus can be defined as the area of the ring-shaped space between two concentric circles that define it.

The area of Annulus can be derived by using the formula mentioned underneath:

         where:
                                          R is the radius of the outer circle
                                          H is the radius of the inner 'hole'
                                          π is Pi, approximately 3.142

This simplifies a little to:

Types of Geometry

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2 D Geometry Formulas

	Square
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	Ellipse
	Annulus
	Regular Polygon

3 D Geometry Formulas

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	General Cone of Pyramid
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Postulates and Theorems

	Point-Line-Plane Postulate
	Euclid's Postulates
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	Euclid's Theorem
	Line Intersection Theorem
	Betweenness Theorem
	Pythagorean Theorem
	Right Angle Congruence Theorem

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