Yes, and 3rd root of is 6th root of 8.
I am just wanting to see if the book may have made a typo. When asking for the three cubed roots of z=-2+2i, we get sqrt(8) for r. the next step shows 6th root of 8 *((cos 135 + 360k)/(3) + i sin (135 + 360k)/(3)). I understand how to get everything here except for the 6??? Shouldn't nth root of r be 3rd root of sqrt (8)????