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In this video, we'll use domoff's theorem to find the power of a complex number and write that complex number in rectangular form.
00:10
Here our complex number is radical 2 cosine 5 pi over 6 plus i sign 5 pi over 6.
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And when i want to raise this to the fourth power, dumao's theorem says that our radius, radical 2, can be raised to the fourth power.
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And our angle 5 pi over 6 will be multiplied by 4.
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To get 20 pi over 6.
00:43
Simplifying that a bit, we have 4 cosine 10 pi over 3 plus i sign 10 pi over 3.
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So we're on a radius, we're on a circle of radius 4.
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So 1, 2, 3, 4.
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And our angle is 10 pi over 3.
01:00
So we'd actually have to go around the circle of a time in a little bit.
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So we go around to 2 pi and then around again to 3.
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Pi over 10 pi over 3.
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So we are here...