powers of complex numbers

Trigonometric ratios and functions, the unit circle, inverse trig functions, identities, trig graphs, etc.
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powers of complex numbers

Postby arletebacon » Tue Oct 11, 2011 2:07 am

use deMoivre's theormen to find the indicated power of the complex number:

2(sqrt3 +2i)^4

what do I do with the 2 in front??
without 2 in front:

r=sqrt(3+4) = sqrt7

tan-1 (2/sqrt3) = 49.1

(sqrt7)^4 (cos(4*49.1) + i (sin(4*49.1)) )

what do I do with the 2????

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Postby stapel_eliz » Tue Oct 11, 2011 11:25 am

what do I do with the 2????
Multiply the complex number by it. :wink:

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