Let f A B and g B C be functions (a) Show that if g f is injective, then f is injective (b) Show that if g f is surjective, then g is surjective

Question: Let f : A B and g : B C be functions. (a) Show that if g f is injective, then f

Let f : A → B and g : B → C be functions.
(a) Show that if g ο f is injective, then f is injective.
(b) Show that if g ο f is surjective, then g is surjective.

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