Surface area of sphere in n dimensions
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17:18
Arithmetic geometric mean inequality
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33:31
The Weak Derivative
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15:51
But why is a sphere's surface area four times its shadow?
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10:33
Strange Spheres in Higher Dimensions - Numberphile
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21:25
Volume of a donut
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27:26
This open problem taught me what topology is
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19:27
How Paul Erdős Cracked This Geometry Problem | The Anning-Erdős Theorem
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12:55