Question

Show that if f : A → B and g : B → C are one-one, then gof : A → C isalso one-​

Answer 1

Solution: Suppose gof (x1) = gof (x2)⇒ g (f(x1))

= g(f (x2))⇒ f(x1) = f(x2), as g is one-one⇒ x1 = x2, as f is one-oneHence, gof is one-one.