No my book never mentioned anything about this, but it makes sense that we have a positive and a negative version of the root. That would give me four if I included the conjugates to the one I wrote, what would the 3rd set be??
Find all complex solutions of z^6 + z^3 + 1
(z^3 + 1)/(z^3 - 1) = i
The Attempt at a Solution
I am going crazy with trial and error with these, there must be some systematic method or tricks that I am oblivious of. For the second question I...
It seems so, but the unit interval has cardinality c and at first glance it appeared to me that we were excluding a finite set from an infinite one, and if I am not mistaken with cardinal arithmetic, c would remain the cardinality. But it seems to be otherwise now.