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May 18th, 2018, 06:43 AM   #1
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help with complex numbers

Hello, I would be happy to help with complex numbers:
Find equation solutions:
https://ibb.co/ceJ06J
Thanks
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May 19th, 2018, 11:37 AM   #2
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$z^3 + 3i \bar{z} = 0$

first off it should be clear that $z=0$ is a solution

Now assume $z\neq 0$

rewrite the equation as

$r^3 e^{i3x}+3e^{i\pi/2}re^{-x}=0$

I leave it to you to show that $r=\sqrt{3}$

Given that, you can remove $r$ from the equation and solve for all of the $x$

I leave it to you to show that they are

$x \in \{5,~7,~9,~13,~15\} \cdot \dfrac \pi 8$
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May 21st, 2018, 07:07 AM   #3
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Should not I first find the r and the angle?
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