/sci/ - Science & Math

>>12304481
>Does this make any sort of sense?
Nah. IIRC this one went like:
Define [math]\phi : Hom_{\mathbb{Z}}(R, A) \rightarrow A[/math] by [math]\phi(f) = f(1)[/math]. Then, the isomorphism is [math]\Phi : Hom_R (M, Hom_{\mathbb{Z}}(R, A)) \rightarrow Hom_{\mathbb{Z}}(M, A)[/math] defined by [math]\Phi : f \rightarrow \phi \circ f[/math]