Talk:Mathematical Proof/Methods of Proof/Proof by Contradiction
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[edit] More Classical examples?
The proof that there are infinite many prime numbers p1,p2,...,pn can be done really elegant by assuming that there are only a finite nunmer of primes, and thet construct a new number (p1*p2*...*pn +1)
that is not divisible by any of the original primes, and therefore, must be either a new prime, or a product of new primes.
Who is the audience for this? If somebody doesn't know what a proof by contradiction is, then they are certainly not going to understand what a topological space is.