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How to solve this equation? ($z$ is a complex number)

$1-z+z^2-z^3=0$

I tried using $z=a+ib$ and reached an answer but I'm not sure if it's a correct one.

Thanks!

imranfat
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    I happen to see that $z=1$ is a solution...What do you think you can do with that? – imranfat Nov 25 '15 at 16:40
  • If you think that you have an answer then you should be able to check it by plugging it in to the original equation – Andy Nov 25 '15 at 16:40

2 Answers2

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$$1-z+z^2-z^3=(1-z)(1+z^2)=0$$ $$z=1,\pm i$$

Kay K.
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$1-z+z^2-z^3=0 $ is equivalent to $(1-z)(1+z^2)=0$,

then $(1-z)(i-z)(i+z)=0$. So, the solutions are:

$z=1$, $z=i$ or $z=-i$

hachemy
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