&Theorem 3.5: Let f be an everywhere function from a to B. Then 令(1)f i)lB°f=f o Proof Concerning(i), let aEA, o IA(a? -fa) g Property (ii) is proved similarly to property ()❖ Theorem 3.5: Let f be an everywhere function from A to B. Then ❖ (i)f IA =f. ❖ (ii)IB  f = f. ❖ Proof. Concerning(i), let aA, (f  IA)(a) ?=f(a). ❖ Property (ii) is proved similarly to property (i)