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Pythagorean theorem

A relationship you can see.

Right triangle with sides a, b, and c Side a is vertical, side b is horizontal, and side c is the hypotenuse. a b c

a2 + b2 = c2

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Pythagorean theorem

A visual proof using areas.

a2 + b2 = c2

Infinite geometric series

Watch each part approach one whole.

1/2 + 1/4 + 1/8 + … = 1