\[A\] to\[B\] for\[C\] on\[D\] in

试证明：

(A∪B∪C)\(A∩B∩C)=(A△B)∪(B△C).

A.(AÍB)∧(B∈C) Þ A∈C

B.(A∈B)∧(B∈C) Þ A∈C

C.(A∈B)∧(B∈C) Þ A Ï C

D.(AÍB)∧(BÍC) Þ AÍC

A.a=b=c

B.a≠b≠c

C.a=b≠c

D.a≠b=c

A) on

B) with

C) to

D) by

A.A´B = B´A

B.(A´B)´C = A´(B´C)

C.A´(B∪C) = (A´B)∪(A´C)

D.如果A´C Í B´C，则A Í B