What is a double root?

A double root is a type of root in algebraic equations where a single solution is repeated twice. It can be identified by looking at the discriminant of the quadratic equation, or by observing that the graph of the equation touches the x-axis at only one point. Double roots have a special significance in certain situations. For example, in the context of differential equations, a double root indicates a repeated solution which can provide insight into the behavior of the system. In general, the algebraic properties of a double root depend on the context in which it arises, and can have important implications for the solution or analysis of the problem at hand.