ProofAsOneWouldWriteItLetfABandgBAbeinjectionsLetA0AandB0BandbyinductionwedeneAi1gBiandBi1fAiLetA0Ti2NAiandB0Ti2NBiThendenehxfxifx2A0Si2NA2inA2i1g1xotherwiseWeclai ID: 607778
ProofAsOneWouldWriteIt.Letf:A!Bandg:B!Abeinjections.LetA0=AandB0=BandbyinductionwedeneAi+1=g[Bi]andBi+1=f[Ai].LetA0=Ti2NAiandB0=Ti2NBi.Then