Комплекс тоо цуврал хичээл-2Март This document discusses complex numbers and their properties in Mongolian. It defines the modulus of a complex number a + bi as √(a2 + b2). It provides examples of calculating the modulus of 3 + 2i and 4 - 5i. It then discusses the conjugate of a complex number a - bi. Other topics covered include complex number addition, multiplication, division, powers, and properties of polynomials with complex number coefficients. Worked examples are provided to illustrate these concepts and theorems.