At: one2one preserves fin11111111111112111111 1. T: Type 2. U: Type 3. f: TU 4. g: UT 5. g o f = Id 6. f o g = Id 7. n: 8. f1: nT 9. Inj(n; T; f1) 10. b: U 11. a: n 12. f1(a) = g(b) 13. f(f1(a)) = f(g(b))
a:n. (f o f1)(a) = b By: RWH add_composeC 13 Generated subgoal: