#Can a โ„ค-module always be extended to a โ„š-module?

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novel matrix
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Basically the title. I'm trying to either show that any finite abelian group ๐บ considered as a โ„ค-module can be extended to a โ„š-module or find a counterexample.

It seems like just letting ๐‘€ be formal โ„š-linear finite sums of elements of ๐บ (and identifying things like ๐‘Ž๐‘”โ‚ + ๐‘Ž๐‘”โ‚‚ with ๐‘Ž๐‘”โ‚๐‘”โ‚‚ where ๐‘Žโˆˆโ„š) gives a module, but I'm afraid it doesn't extend ๐บ because it collapses something it shouldn't or somewhere in there.

worldly sorrelBOT
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novel matrix
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It seems like we could potentially let ๐‘€ be the regular โ„š๐บ-module then quotient ๐‘€ by things we want to be the same? I'm not sure; this exercise is confusing

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+close

hexed oarBOT
# novel matrix +close
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