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Find all cube roots of 64 (cos 219 degrees +i sin 219 degrees)

User Sergey G
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1 Answer

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The principal root is
(64∠219°)^(1/3) = (64)^(1/3)∠(219°/3) = 4∠73°

The other two roots are 120° and 240° from this, so the three roots are
4∠73°
4∠193°
4∠313°
User Memius
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