Uploaded July 2026 | Updated September 2026, 2 weeks ago

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In this video, we trace the fascinating history of how mathematicians discovered the formula for the area of a circle. Beginning with an introduction, we explore the geometric relationship between area and perimeter, showing how these ideas connect. The lesson then highlights ancient approaches, culminating in Archimedes’ brilliant proof, which laid the foundation for modern understanding of circle area.

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khanacademy.org/math/ncert-math-class-9-new/x56891bfac37feca0:measuring-space-perimeter-and-area

Timestamps:
00:00 Introduction
00:47 Geometric relation between area and perimeter
03:08 Ancient calculations and Archimedes' Proof

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