What is a radical, and how is it expressed mathematically?

A radical is a mathematical expression that involves the root of a number. The most common type of radical is the square root, but there are also cube roots, fourth roots, and so on. Mathematically, a radical is expressed using the radical symbol (√) followed by the number or expression under the root. The general form of a radical can be written as: \[ \sqrt[n]{a} \] where: - \( n \) is the index of the root (for example, \( n = 2 \) for square roots, \( n = 3 \) for cube roots, etc.), - \( a \) is the radicand (the number or expression under the radical). For example: - The square root of 9 is expressed as \( \sqrt{9} \) and equals 3. - The cube root of 8 is expressed as \( \sqrt[3]{8} \) and equals 2. In summary, a radical represents the operation of finding a root of a number or expression, and it is expressed using the radical symbol along with the index and radicand.