A radical expression is a mathematical expression that includes a root symbol, such as the square root (√) or cube root (∛). These expressions are used to represent numbers that cannot be expressed as simple fractions or whole numbers. For example, √4 equals 2, but √2 is an example of a radical expression that cannot be simplified to a whole number. Radical expressions can be simplified by finding perfect squares or cubes within the radicand (the number under the root). Operations such as addition, subtraction, multiplication, and division can also be performed on radical expressions, following specific rules. Understanding these expressions is essential in algebra and higher-level mathematics, where they frequently appear in equations and functions.