# 8.2: Irrational Numbers

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Definition: Irrational

A number that is not a rational number is called an irrational number.

Theorem $$\PageIndex{1}$$

$$\sqrt{3}$$ is irrational.

Proof

Example $$\PageIndex{1}$$:
Prove that $$\sqrt{3+\sqrt{6}}$$ is irrational.