After taking |A|=0, I am getting x3+1=0 and not x3-1=0.
Is it x3+1=0 or x3-1=0?
Ya, i missed the '-' in multiplying 2nd parameter.
BTW, expansion of (x3-1) is (x-1)(x2+x+1), so x=1, and not -1, for real values of x.
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