# Precalculus

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Write the three cube roots of 8 cis (-30°).

• Precalculus -

2 e^i(-30/3) = 2 cis -10
2 e^i(-30/3 +360/3)= 2 cis 110
2 e^i(-30/3 -360/3) = 2 cis -130

• Precalculus -

This is probably silly, but where is the 2 in the beginning of all of those from?

• Precalculus -

2*2*2 = 8

• Precalculus -

Ohmygoodness. Hhaha. Thanks!

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