Complex number that is the root of a non-zero polynomial with rational coefficients.
Numbers such as π, sin(1), e, 2sin(3) are not algebraic numbers. They are called transcendental numbers.
Example
The number \(\sqrt{7}\) is an algebraic number, since it is the root of the equation : \({x^2}– 7 = 0\).
The complex (imaginary) number \(2\)i = \(2\sqrt{-1}\) is an algebraic number because it is the solution to the equation x2 + 4 = 0.