fundamental theorem of algebra

fundamental theorem of algebra, theorem of equations proved by Carl Friedrich Gauss in 1799. It states that every polynomial equation of degree n with complex number coefficients has n roots, or solutions, in the complex numbers. The roots can have a multiplicity greater than zero. For example, x² − 2x + 1 = 0 can be expressed as (x − 1)(x − 1) = 0; that is, the root x = 1 occurs with a multiplicity of 2. The theorem can also be stated as every polynomial equation of degree n where n ≥ 1 with complex number coefficients has at least one root.