Short Exact Sequence

An exact sequence of the form $0\to A\stackrel{f}{\to }B\stackrel{g}{\to }C\to 0$, where $f$ ang $g$ are Homomorphisms Since this is an exact sequence, we have that:

• $f$ is a monomorphism, i.e. it is an injective Homomorphism.
• $g$ is an epimorphism, i.e. it is a surjective Homomorphism.
• $imf=\ker g$, i.e. the image of $f$ equals the Kernel trick of $g$.

Visual representation of exact sequences