# Why is the Square Root of 2 Irrational?

Here is a minimalist step-by-step proof with simple explanations that the square root of 2 is an irrational number. Thousands of years ago, Greek mathematicians discovered that there are irrational numbers. The following proof is a classic example of proof by contradiction. We will assume that our claim is not true, and then we will come to a contradiction. Since there are no contradictions in mathematics, we must accept that our claim is true.

If you enjoy math proof, you should check out this beautiful book list, “70 Best Math Books to Learn Writing Mathematical Proofs.”

### Ali Kaya

This is Ali. Bespectacled and mustachioed father, math blogger, and soccer player. I also do consult for global math and science startups.

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