Topic related to complex numbers and sequence and series.

[raven elm]

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[proper gorge]

looks like an induction proof

[solar hawk]

plzzz help brooo

[proper gorge]

n=1 is true, yes?

[solar hawk]

yes

then?

[proper gorge]

do induction

assume is true for n and show that is also true for n+1

show is true for n=2 for example

that will give you an idea how to prove general case

[solar hawk]

okayyy

[errant sleet]

$z=\norm{z}\cdot\text{Cis}\qty(\arctan\qty(\frac{\Im(z)}{\Re(z)}))$

[cobalt swift]

Cofailure

[errant sleet]

what is e^(ix)?

[proper gorge]

im not entirely sure of that

$$ z= |z| \mathrm{cis}(\arg z) $$

[cobalt swift]

aL

[proper gorge]

this would be correct

[proper gorge]

if the ratio is negative you get something in (-pi/2, 0) after taking arctan, so effectively you would be putting all those complex numbers in the 4th quadrant

but that's only true in the event that im z < 0 and re z > 0