A demonstration of the Pythagoras' theorem [Une démonstration du théorème de Pythagore].
Surface(Green Square) = Surface(Red Square) + 4.Surface(Blue Triangle)= +
2 2 1 (X+Y) = Z + 4.(---.X.Y) 2
___ ___ 2 2 / \ 2 / \ X + Y + 2.X.Y = Z + 2.X.Y \___/ \___/
2 2 2 X + Y = Z
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