English
The composition of prodComparison along F and G equals the sequential coproducts: prodComparison (F ⋙ G) A B = G.map (prodComparison F A B) ≫ prodComparison G (F.obj A) (F.obj B).
Русский
Композиция prodComparison по F и G равна последовательному копродукту: prodComparison (F ⋙ G) A B = G.map (prodComparison F A B) ≫ prodComparison G (F.obj A) (F.obj B).
LaTeX
$$$ \\operatorname{prodComparison} (F \\cdot G) A B = G.map (\\operatorname{prodComparison} F A B) \\circ \\operatorname{prodComparison} G (F.obj A) (F.obj B) $$$
Lean4
theorem prodComparison_comp :
prodComparison (F ⋙ G) A B = G.map (prodComparison F A B) ≫ prodComparison G (F.obj A) (F.obj B) :=
by
unfold prodComparison
ext <;> simp [← G.map_comp]