Square Root 272F04

1. The problem is to understand the expression $\sqrt{x}$, which represents the square root of $x$. 2. The square root of a number $x$ is a value that, when multiplied by itself, gives $x$. 3. The formula for the square root is $y = \sqrt{x}$, meaning $y^2 = x$. 4. Important rules: - $x$ must be non-negative for real numbers, i.e., $x \geq 0$. - $\sqrt{x^2} = |x|$. 5. Example: If $x = 9$, then $\sqrt{9} = 3$ because $3^2 = 9$. 6. If $x$ is unknown, $\sqrt{x}$ remains as is, representing the principal (non-negative) square root of $x$.