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[demihsieh (Demih)]

這兩題怎麼解?

(一)
1.(A<->~B)orB   /所以 AorB

(二)
1.A<->(B->C)
2.P->Q
3.Q->B
4.PorQ    /所以A<->C

感謝 8)

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→ mikechan:((P->Q)&(Q->B))->(P->B) ((Q->B)&(P->B)&(PorQ))->B
→ mikechan:(A<->(B->C))<->((A->(B->C))&((B->C)->A))
→ mikechan:((A->(B->C))&((B->C)->A))->((A->(B->C))
→ mikechan:((A->(B->C))&((B->C)->A))->((B->C)->A)
→ mikechan:(A->(B->C))<->(~Aor(B->C)) (~Aor(B->C))<->(~Aor~BorC)
→ mikechan:((B->C)->A)<->(~(B->C)orA) (~(B->C)orA)<->~(~BorC)orA
→ mikechan:(~(~BorC)orA)<->((B&~C)orA)
→ mikechan:((B&~C)orA)<->(BorA)&(~CorA)
→ mikechan:((BorA)&(~CorA))<->(~CorA) (~CorA)<->C->A
→ mikechan:((BorA)&(~CorA))<->(~CorA) (~CorA)<->(C->A)
→ mikechan:((~Aor~BorC)&B)<->(~AorC) (~AorC)<->(A->C)
→ mikechan:((C->A)&(A->C))<->(A<->C)
→ mikechan:好混亂...
→ mikechan:(A<->~B)orB -> ((A->~B)&(~B->A))orB
→ mikechan:((A->~B)&(~B->A))orB <-> (((A->~B)orB)&((~B->A)orB))
→ mikechan:(((A->~B)orB)&((~B->A)orB))->((A->~B)orB)
→ mikechan:(((A->~B)orB)&((~B->A)orB))->((~B->A)orB)
→ mikechan:((~B->A)orB)<->(BorAorB)  (BorAorB)<->AorB
→ mikechan:我覺得我自己也會看到昏掉
→ maylaw:現在作業不會寫都上來問就好了？板友真是佛心來地呀～
→ demihsieh:有點眼花可是謝謝