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How to Calculate Complex Numbers

What is Complex Numbers?

A complex number z = a + bi combines real part a and imaginary part b, where i = √(−1). Complex numbers extend the real line to a 2D plane and are essential in engineering, physics, and signal processing.

Step-by-Step Guide

  1. 1Addition: (a+bi)+(c+di) = (a+c)+(b+d)i
  2. 2Multiplication: (a+bi)(c+di) = (ac−bd)+(ad+bc)i
  3. 3Magnitude |z| = √(a²+b²) · Argument θ = atan2(b,a)

Worked Examples

Input
(3+4i) × (1−2i)
Result
11−2i · |z|=√125
(3+8)+(4-6)i=11-2i

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