Fundamental theorem of algebra

Abstract

The purpose of the article is to familiarize teachers and students with the fundamental theorem of algebra for real polynomials and its proof. Polynomials of small degrees are considered separately. It is showed how equations of the third and fourth degree can be solved. An algorithm for solving cubic equations is proposed.

Keywords

• real polynomials
• fundamental theorem of algebra
• decomposition of polynomials
• sine and cosine of multiple argument
• cubic equations
• equations of the fourth degree