Complex number is an important concept in mathematics, which is usually expressed in the form of a+bi, where A and B are real and imaginary parts respectively. In the process of learning complex numbers, there are some important secondary conclusions to master. The following is a brief introduction to these conclusions.

Complex * * * yoke: For any complex number a+bi, its complex number of * * * yoke is a-bi. * * * yoke's complex number plays an important role, such as calculating the square of the module length and solving complex equations.

Modulus length of complex number: for a complex number a+bi, its module length is defined as | A+Bi | = sqrt (A 2+B 2), which indicates the distance from the complex number to the origin, and can also be understood as the size of the complex number. Modulus length has many practical applications, such as calculating the length of vectors.

Polar angle of complex number: For a complex number a+bi, the angle between the corresponding point on the complex plane and the real axis is called its polar angle, which is usually expressed by θ. Polar angles are directional and can be divided into positive and negative points, which can be used to describe the direction of vectors.

Power of complex number: For a complex number a+bi, the power of n can be expressed as (A+BI) n = | A+BI | n (COS (nθ)+ISIN (nθ)). This formula can be used to calculate the power of a complex number, and it has many practical applications, such as calculating the AC voltage in a circuit.

These secondary conclusions are the basic concepts of complex numbers, which need to be deeply understood and mastered in the process of learning complex numbers.