离散数学试卷（四）
⑸?x(M(x)??y(G(y)??H(x,y))) ⑹M(a)??y(G(y)??H(a,y)) ⑺?y(G(y)??H(a,y)) ⑻?y(H(a,y)??G(y)) ⑼F(z)?H(a,z) ⑽H(a,z)??G(z) ⑾F(z)??G(z) ⑿?x(F(x)??G(x))
四、 证明10%
P US⑸ T⑶⑹I T⑺E US⑷ US⑻ T⑼⑽I UG⑾
?xA(x)??xB(x)?(A(a)?A(b)?A(c)?(B(a)?B(b)?B(c)?(A(a)?B(a))?(A(a)?B(b))?(A(a)?B(c))
?(A(b)?B(a))?(A(b)?B(b))?(A(b)?B(c))?(A(c)?B(a))?(A(c)?B(b))?(A(c)?B(c))?(A(a)?B(a))?(A(b)?B(b))?(A(c)?B(c)??x(A(x)?B(x))
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