I didn't understand why in this definition $I$ has to be an ideal to make sense.
REMARK
This is from Steps in Commutative Algebra, page 107.
Thanks a lot
2026-05-06 03:17:32.1778037452
Help with this definition of $(G:_M I)$
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The definition doesn't claim that $I$ has to be an ideal, and in fact it doesn't, but if $S$ is any subset of $R$ then $(G :_M S) = (G :_M I)$ where $I$ is the ideal generated by $S$, so $I$ might as well be an ideal.