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MercuryRising
Nov24-04, 08:56 PM
Z^6 + 64 = 0
there are suppose to be 6 solutions :confused:
need help on how to find the roots

vsage
Nov24-04, 09:32 PM
Are you familiar with de Moivre's theorem? The problem is pretty easy then. Alternatively, you can factor the equation Z^6 + 64=0 into
(Z^3 - 8i)(Z^3+8i) from which you can factor more.

MercuryRising
Nov24-04, 10:02 PM
opps, sorry, i must 've made myself unclear, the goal is to find the 6 values of z, but thanks for heling on the roots! :smile:

Gokul43201
Nov24-04, 11:43 PM
Write z^6 = r^6(cos 6\theta + isin 6\theta) and solve.

nolachrymose
Nov25-04, 09:44 AM
opps, sorry, i must 've made myself unclear, the goal is to find the 6 values of z, but thanks for heling on the roots! :smile:

Vsage's point was that, from there, you can factor further, thus getting the six linear roots (hint: think about sum and difference of cubes).