Algebraic number
An algebraic number is a zero of a polynomial.
Explanation
An algebraic number is a root of an equation in the form
in which the coefficients a0, a1, ... an are all integers.
Examples
1. All rational numbers are algebraic because the fraction a / b is a solution of bx – a = 0.
2. The irrational number √2 is algebraic because it is a solution of x2 − 2 = 0.
3. The imaginary unit i is algebraic, as it is a root of x 2 + 1 = 0.