Definition:Quadratic Irrational

Definition
A quadratic irrational is an irrational number of the form:
 * $r + s \sqrt n$

where $r, s$ are rational and $n$ is a positive integer which is not a square.

Also known as
A quadratic irrational is also known as a quadratic surd.

Also see

 * Definition:Quadratic Equation
 * Quadratic Irrational is Root of Quadratic Equation