Is ring R itself a finitely generated module over $R$?

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It seems trivial that ring $R$ itself is a $R$-module. But then can we say R is finitely generated by multiplicative identity? That seems so trivial..

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Yes. We can write $R = (1)$, but notice that it's not necessary that every ideal in $R$ is finitely generated:

Choose $R = k[x_1, x_2, \ldots]$ and let $I = (x_1, x_2, \ldots)$. $R$ is finitely generated since $R = (1)$, but $I$ is not finitely generated.