Introduction to Complex Numbers

Numbers that extend the real number system to include square roots of negative numbers.

The Imaginary Unit

Defined as $i = \sqrt{-1}$, so $i^2 = -1$.

Complex Numbers

A complex number has the form $z = a + bi$, where $a$ is the real part and $b$ is the imaginary part.

Modulus and Argument

The modulus of $z = a+bi$ is $|z| = \sqrt{a^2+b^2}$, representing its distance from the origin on the complex plane.

Lesson 8 of 27
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