以下各式成立的是( )
A、∀x(¬A(x)→B(x)),∀x¬B(x)⇒∃xA(x)
B、∃xA(x)→∀xB(x)⇒∀x(A(x)→B(x))
C、∀x(A(x)→B(x)),∀x(C(x)→¬B(x))⇒∀x(C(x)→¬A(x))
D、∀x(A(x)∨B(x)),∀x(B(x)→¬C(x)),∃xC(x)⇒∀xA(x)
发布时间:2024-09-12 15:52:42
A、∀x(¬A(x)→B(x)),∀x¬B(x)⇒∃xA(x)
B、∃xA(x)→∀xB(x)⇒∀x(A(x)→B(x))
C、∀x(A(x)→B(x)),∀x(C(x)→¬B(x))⇒∀x(C(x)→¬A(x))
D、∀x(A(x)∨B(x)),∀x(B(x)→¬C(x)),∃xC(x)⇒∀xA(x)