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bigreddog
Aug23-08, 10:14 PM
Let A be the integers modulo 7.
b(x)= x^3 -2 and c(x) = x^3 + 2 are polynomials in A[x].

How can you show that A/<b(x)> and A/<c(x)> have the same number of elements? In this practice problem I already showed that A/<b(x)> and A/<c(x)> are fields by showing that <b(x)> and <c(x)> are maximal ideals, but I don't know how this helps.

mathwonk
Aug24-08, 05:14 PM
you stated it wrong it seems. you want A[x]/<whatever>. then it gets easier.