Question regarding finitely generated modules

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The discussion centers on the equivalence of properties for finitely generated modules, specifically showing that a finitely generated module P is projective if and only if it is isomorphic to a direct summand of a free module. The user is attempting to demonstrate the implication from projective to being a direct summand, utilizing the homomorphism α: M -> P and the relationship between M, ker(α), and K, a subset of P. The user acknowledges a misunderstanding in their definition of projective modules, which states that a module P is projective if for any surjective homomorphism f: M -> P, the module M can be expressed as the direct sum of ker(f) and a submodule K contained in P.

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I am supposed to show that the following are equivalent for a finitely generated module P:

1. P is Projective
2. P is isomorphic to direct summand of a free module
(There are 2 others but they refer to a diagram)

I am stuck on showing 1 => 2.

I know that since P is projective there is α: M -> P so that
M is isomorphic to ker (α) (direct sum) K,
where K is a subset of P.
Also since P is finitely generated P = Rx1 (direct sum) … (direct sum)Rxn.

I also know that K is isomophic to M/ker(α)

I believe I need to show that P = K, because then P would be isomorphic to a direct summand, but I don’t know how to show this.
 
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I have recently noticed that my definition of Projective is incorect.
A module P is projective provided:
If f:M -> P is a homomorphism and onto then M = ker(f) (direct sum) K,
K contained in P.

Hopefully that makes my question easier.
 

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