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Formula

Cube roots of unity in determinants

ω3=1,1+ω+ω2=0\omega^3 = 1, \qquad 1 + \omega + \omega^2 = 0
ω\omega
a non-real cube root of unity

Determinants built from cube roots of unity collapse through these two relations, usually by adding all columns so one becomes zero.

20
questions use it
5
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2017–2026
years it has appeared
50%
rated HARD
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