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# Irrational Fraction

Pro Problems > Math > Logic > Proofs > Indirect Proofs

## Irrational Fraction

Let a and b be positive integers, with b not a perfect square. Show that the following expression is irrational, using an indirect proof.

a +
b
a -
b

Hint: Remember that an irrational number is a number which cannot be written as the quotient of two integers.

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Problem by Mr. Twitchell

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