Question

What is an example of complex conjugate?

Answer 1

Rectangular form of a complex number:

The rectangular form a complex number is $a+ib$, where $a$ is real part and $bi$ is imaginary part.

Complex conjugate:

The real part of complex number and conjugate complex number are the same.

The magnitude of imaginary part is also the same but the signs are opposite.

In another word, the refection of a complex number with respect to the real line is the complex conjugate.

The conjugate of complex number is denoted by $\overline{z}$.

The complex conjugate of the complex number $a+ib$ is $a-ib$.

Example of of complex conjugate:

Let $z=9-21i$ be a complex number.

The complex conjugate of the complex number is $\overline{z}=9+21i$.