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Roots of unity product set size

1925SpecialistComplex NumbersNumber Theory

AIME · 1990 · Problem 10

The sets $A = \{z : z^{18} = 1\}$ and $B = \{w : w^{48} = 1\}$ are both sets of complex roots of unity. The set $C = \{zw : z \in A ~ \mbox{and} ~ w \in B\}$ is also a set of complex roots of unity. How many distinct elements are in $C^{}_{}$?
0 students attempted0% solvedRating 1925

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