In polar form, 8 = 8 (cos0° + j sin0°).

There are 3 roots, so they will be θ = 120° apart.

Using DeMoivre's Theorem:

an = rn(cos nθ + j sin nθ),

First root:

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Second root: Add 120° to the first root:

81/3(cos120° + jsin120°) = -1 + 1.732j

Third root: Add 120° to the second root:

81/3(cos240° + jsin240°) = -1 - 1.732j

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So the 3 cube roots of 8 are:

2, -1 + 1.732j, and -1 - 1.732j.