Proofs by contradiction.
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a cornucopia of proofs!
8:57
Proving statements false.
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The contrapositive.
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Proof by Contradiction: log₂5 is irrational
16:43
The 379 page proof that 1+1=2
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Geometry: Beginning Proofs (Level 1 of 3) | Algebra Proofs, Geometric Proofs
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EL JUEGO DE LA VIDA DE CONWAY
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