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Use Demoivres Theorem to find (-square root 3 +i)^6

Use Demoivres Theorem to find (-square root 3 +i)^6-example-1
User Ikkez
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2 Answers

3 votes

Answer:

A) -64

Explanation:

Edge 2021

Use Demoivres Theorem to find (-square root 3 +i)^6-example-1
User Sagar Kulkarni
by
4.8k points
6 votes

Answer:


z=(-√(3)+i)^6 = -64

Explanation:

You have the following complex number:


z=(-√(3)+i)^6 (1)

The Demoivres theorem stables the following:


z^n=r^n(cos(n\theta)+i sin(n\theta)) (2)

In this case you have n=6

In order to use the theorem you first find r and θ, as follow:


r=√(3+1)=2\\\\\theta=tan^(-1)((1)/(√(3)))=30\°

Next, you replace these values into the equation (2) with n=6:


z^6=(2)^6[cos(6*30\°)+isin(6*30\°)]\\\\z^6=64[-1+i0]=-64

Then, the solution is -64

User Kishal
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4.7k points