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Tracenoxus

Guest

Help!!!!

Use Mathematical induction to prove DeMoivre's Theorem:

[r(cos(theta)+i sin(theta))]^n=r^n(cos n(theta)+i sin(theta) n(theta))

for every positive integer n.

I help on how to prove that Sk+1 is true for this. Simplifying and everything. Just Sk+1 though. I already proved for S1 and Sk.

luca-deltodesco

Member

Registered: 2006-05-05

Posts: 1,470

Re: Help!!!!

you messed up a little bit in writing it out there

Since you've given it in trigonometric form, i'll keep it in trigonometric form.

n = 0

n = k+1

since:

hence:

qed.

Last edited by luca-deltodesco (2008-06-03 21:07:44)

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