Is a Square Root a Rational Number? The Complete Answer
The short answer to the question "is a square root a rational number" is: it depends on the number under the radical. Worth adding: a square root is rational only when the number inside it is a perfect square (or a perfect square fraction). This leads to for every other positive number, the square root is irrational, meaning it can never be written as a simple fraction. Understanding this distinction is one of the most important milestones in building solid number sense, and this article will walk you through exactly how to tell the difference.
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What Is a Rational Number?
Before we can answer whether a square root is rational, we need a clear definition. A rational number is any number that can be written as a fraction $\frac{a}{b}$, where $a$ and $b$ are integers and $b \neq 0$. The word "rational" comes from "ratio," which is the key clue And it works..
