Lemma 10.89.6. Let $M$ be a flat Mittag-Leffler module over $R$. Let $F$ be an $R$-module and let $x \in F \otimes _ R M$. Then there exists a smallest submodule $F' \subset F$ such that $x \in F' \otimes _ R M$.

**Proof.**
Since $M$ is flat we have $F' \otimes _ R M \subset F \otimes _ R M$ if $F' \subset F$ is a submodule, hence the statement makes sense. Let $I = \{ F' \subset F \mid x \in F' \otimes _ R M\} $ and for $i \in I$ denote $F_ i \subset F$ the corresponding submodule. Then $x$ maps to zero under the map

whence by Proposition 10.89.5 $x$ maps to zero under the map

Since $M$ is flat the kernel of this arrow is $(\bigcap F_ i) \otimes _ R M$ which proves the lemma. $\square$

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## Comments (1)

Comment #8086 by Laurent Moret-Bailly on

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