If z = cos theta + i sin theta, then z³ + 1/ z³ =

Answer 1

Hint:

If Z = r(cosθ + i sinθ)

Zⁿ = rⁿ [cos(n.θ) + i sin(n.θ)]

In the above question, given z=(cosθ + i sinθ)

Here, r=1

thus, Z³ = 1³ [cos(3.θ) + i sin(3θ)]

Now, solve for Z³ + 1/Z³