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juliany
Nov19-10, 07:27 PM
1. The problem statement, all variables and given/known data
Find the five values of (1+i√3)^(3/5)

This question was from my recent end of year exam, I hadn't come across a question like it in my revision, does it mean find the five roots of (1+i√3)^(3/5) ?:confused:

vela
Nov19-10, 07:32 PM
You want to find the five 5th roots of (1+i√3)3.

Outlined
Nov20-10, 03:07 AM
you want to find all the solutions of the equation X5 = (1 + i√3)3 = -8.

HallsofIvy
Nov20-10, 01:07 PM
It's remarkable that the third power is equal to -8!!

Yes, you can find the five fifth roots of (1+i\sqrt{3})^3 or just apply D'Moivre's theorem to 1+ i\sqrt{3} with n= 3/5.

Outlined
Nov21-10, 01:17 PM
It's remarkable that the third power is equal to -8!!

why?

Mentallic
Nov21-10, 07:19 PM
Because it's a real number. (-2)3=-8 as well so some might be reluctant enough to say that 1+i\sqrt{3}=-2 :tongue: