Complex numbers:General review and De moivre theorem

De Moivre

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CCSS.HSN.CN.B.4

Covert to polar form then solve using DeMoivre's Theorem

• 72 - 72√3i

• - 72√3 + 72i

• - 72√2 + 72√2i

• -72 + 72√3i

Exponential Notation

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Tags

CCSS.HSN.CN.B.4

Arguments

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Loci

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Sum and Product of the Roots

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Tags

CCSS.HSA.APR.B.3

Square Roots of Complex Numbers

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Loci

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Complete and you can post in de Moivre`s assignment box. Label as quizizz question

1)Use de Moivre's theorem to prove that 

 $\sin5x=16\sin^5x-20\sin^3x+5\sin x$  

Complete and you can post in de Moivre`s assignment box. Label as quizizz question

2(i)  Write the complex number $z=\left(-1+\sqrt{3}\ i\right)^7$ in the form  $z=r\ e^{i\theta}$  where  $r=\left|z\right|$  and  $\theta=\arg\left(z\right)$  . 

(ii) Hence, prove that  $\left(-1+\sqrt{3}\ i\right)^7=64\left(-1+\sqrt{3}\ i\right)$