Proof That The Square Root Of Two Is Irrational.

Here is a proof that √2 cannot be written as a fraction and hence is irrational:
  • Every rational has a reduced form.
  • A reduced form cannot have two evens.
  • Every square of an odd is an odd.
  • Every square of an even is an even.
  • If m / n is the reduced form of √2, then m2 = 2n2.
  • That implies m2 is even.
  • That implies m is even.
  • That implies m = 2k for some integer k.
  • That implies n2 = 2k2 for some integer k.
  • That implies n2 is even.
  • That implies n is even.
  • m and n cannot both be even.
  • m / n does not exist.
  • 2 cannot be written as a fraction.
  • QED

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