###### Definition1.1.7Complex Number

A complex number is a number that can be expressed in the form $$a + bi\text{,}$$ where $$a$$ and $$b$$ are real numbers and $$i$$ is the imaginary unit. In this expression, $$a$$ is the real part and $$b$$ (not $$bi$$) is the imaginary part. You can read more at en.wikipedia.org/wiki/Complex_number.

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