Complex Roots of Equations: Solving z^3 = -8i

[littlewombat]

De Moivre's theorem~~HELP~

Homework Statement

Solve the following equations


z^3=-8i


Can anyone please tell me how to solve this problem?

 

[Mentallic]

You can use De Moivre's theorem (actually, are you meant to?) but there is an easier way to solve it.

Notice that $$-8i=\left(2i\right)^3$$

 

[Apphysicist]

Homework Statement

Solve the following equationsz^3=-8iCan anyone please tell me how to solve this problem?

Z=cuberoot(-8i)

So write (-8i) in r*e^(i*theta) form and then raise it to the one-third...then consider all the angles that theta could be as you round the unit circle once.

EDIT: I like Mentallic's way, haha.

 

[Mentallic]

EDIT: I like Mentallic's way, haha.

Haha thanks