Geometric Derivation and Unfolding of Circle Area
2020-11-04 07:45
This applet demonstrates the geometric derivation of the circle area formula. By dividing a circle into sectors and rearranging them, it visually shows how the area unfolds into an approximate rectangle. Users can observe the limiting process as the number of divisions increases, helping students understand the formula's geometric meaning and basic calculus concepts.
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1. 分割成全等的扇形
2. 先旋转后平移
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4. 得出圆面积公式
$\approx$平行四边形面积
逼近长方形面积
5. 细分到无穷时，长方形的长
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