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# Division of complex numbers calculator

Use this online calculator to divide complex numbers.
The calculator shows a step-by-step, easy-to-understand solution on how the division was done.

Division of complex numbers calculator
learn how to divide complex numbers
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$\dfrac{3-2i}{4+5i}$
$\dfrac{\frac{1}{2}-i}{2+\sqrt{2}i}$
working...
EXAMPLES
example 1:ex 1:
Divide $\left( 2 - 6i \right)$ by $\left( 1 + i \right)$.
example 2:ex 2:
Divide $\left( \dfrac{1}{2} - 2i \right)$ by $\left( 2 - i \right)$.
example 3:ex 3:
Divide complex numbers $\,\,\dfrac{ 2 - 3i}{ \sqrt{2} + i}$
TUTORIAL

## How to divide complex numbers?

This calculator uses multiplication by conjugate to divide complex numbers.

### Example 1:

$$\frac{ 4 + 2i }{1 + i}$$

We begin by multiplying numerator and denominator by complex conjugate of $\color{purple}{1 + i}$.

$$\frac{4 + 2i}{\color{purple}{1 + i}} \cdot \frac{\color{blue}{1 - i}}{\color{blue}{1 - i}} = \frac{(4+2i)(1-i)}{(1+i)(1-i)}$$

Then we expand and simplify both products. Keep in mind that $i^2 = -1$.

\begin{aligned} \frac{(4+2i)(1-i)}{(1+i)(1-i)} &= \frac{4 - 4i + 2i - 2\color{blue}{i^2}}{1+i-i-i^2} = \\[ 1 em] &= \frac{4 - 2i - 2\color{blue}{(-1)}}{1-\color{purple}{i^2}} = \\[ 1 em] &= \frac{4 - 2i + 2)}{1-\color{purple}{(-1)}} = \\[ 1 em] &= \frac{6 - 2i)}{2} \end{aligned}

At the end we separate real and imaginary parts:

$$\frac{6 - 2i}{2} = \frac{6}{2} - \frac{2}{2}i = 3 - i$$

### Example 2:

Divide $10 - 25i$ by $5i$

Although the complex conjugate of $5i$ is $-5i$, we can simplify division process by multiplying numerator and denominator with $- i$.

\begin{aligned} \frac{10-25i}{5i} &= \frac{10-25i}{5i} \cdot \frac{-i}{-i} = \\[1 em] &= \frac{(10-25i)(-i)}{(5i)(-i)}= \\[ 1 em] &= \frac{-10i + 25i^2}{-5i^2} = \\[ 1 em] &= \frac{-10i - 25}{5} = \\[ 1 em] &= \frac{-25}{5} + \frac{-10}{5} i= \\[ 1 em] &= -5 - 2 i= \\[ 1 em] \end{aligned}

### Example 3:

Divide $20 + 10i$ by $1 - 3i$

Solution

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