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The cokernel of a module homomorphism $f:A\to B$ is the quotient module $B/\operatorname{im}(f)$. It represents the codomain modulo the image of the map.

Conditions: $f:A\to B$ is a homomorphism of $R$-modules.

The cokernel of a module homomorphism $f:A\to B$ is the quotient module $B/\operatorname{im}(f)$. It represents the codomain modulo the image of the map.

Conditions: $f:A\to B$ is a homomorphism of $R$-modules.