The sheafification functor is a left-adjoint to the forgetful functor. Hence it commutes with colimits. The cokernel is a colimit. Hence the cokernel of a sheafified morphism is the same as the sheafified cokernel. This is obviously false. Where was my mistake?
2026-03-29 20:18:47.1774815527
Mistake in contradiction argument to show that sheafification commutes with cokernel
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