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Proof by Contradiction

Proof by Contradiction
Indirect Proof

Proving a conjecture by assuming that the conjecture is false. If this assumption leads to a contradiction, the original conjecture must have been true. This technique employs the logical method known as modus tolens.

 

Proof by contradiction that √2 is irrational: assumes √2=a/b, derives 2b²=a², showing 2 divides both a and b, contradicting...

 

 

See also

Irrational, rational, integer, factor, relatively prime