More EX2 Help needed (1 Viewer)

ExtremelyBoredUser

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More questions that I can't seem to get.
Question 4:

z^n = 2^n * [ cos(5npi/6) + isin(5npi/6) ], by De Moivre's Theorem.

For z^n to be real, Im(z) = 0:

sin(5npi/6) = 0
5npi/6 = 0

Now its asking for lowest positive integer value, for the sin component to be 0, the value inside it must be pi. Hence n is 6 since it is the lowest positive integer value that produces 0.

I'll solve Q2 after my online school finishes today but I have an idea for it.
 

idkkdi

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2:
(multiply bottom and top by |z|)
|z|^2 = z\bar{z}
(factor)

(cross multiply kinda)
(times top and bottom by z)
|z|^2 = z\bar{z}
(square both sides)
if u do it this way, how would you go about justifying it not being

?

More questions that I can't seem to get.
cartesian bashing that question is disgusting.
If you are going to bash it, it only seems doable if you do,
Required to prove: |z|(z+|z|) = z(z_bar+|z|)
 
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