要考高级数理逻辑了,和舍友整理了一波去年高级数理逻辑的答案,可能有错误。仅供参考,被坑了,概不负责。嘿嘿嘿。参考了王元元的《现代逻辑学》,李文生老师的PPT,和BigPan老师的讲义,北邮科技酒店的往年试题集合。

  1. 修改了简答题第一题中的问题,有朋友指出 \begin{aligned} C^* &= \neg(\Diamond A \rightarrow \Diamond B)^* \land (\Diamond(A \rightarrow B))^* \\ &= \neg(\neg(\Diamond A)^* \land (\Diamond B)^*)) \land \Box(A \rightarrow B)^* \\ &= \neg(\neg \Box A^* \land \Box B^*) \land \Box(\neg A^* \land B^*) \\ &= (\Box A^* \lor \neg \Box B^*) \land \Box \neg(A^* \lor \neg B^*) \\ \neg C^* &= \neg (\Box A^* \lor \neg \Box B^*) \lor \neg \Box \neg(A^* \lor \neg B^*) \\ &= \neg (\Box A^* \lor \neg \Box B^*) \lor \Diamond(A^* \lor \neg B^*) \\ &= \neg(\Box B^* \rightarrow \Box A^*) \lor \Diamond(B^* \rightarrow A^*) \\ &= (\Box B^* \rightarrow \Box A^*) \rightarrow \Diamond(B^* \rightarrow A^*) \end{aligned} C ¬ C = ¬ ( A B ) ( ( A B ) ) = ¬ ( ¬ ( A ) ( B ) ) ) ( A B ) = ¬ ( ¬ A B ) ( ¬ A B ) = ( A ¬ B ) ¬ ( A ¬ B ) = ¬ ( A ¬ B ) ¬ ¬ ( A ¬ B ) = ¬ ( A ¬ B ) ( A ¬ B ) = ¬ ( B A ) ( B A ) = ( B A ) ( B A )

    \begin{aligned} C &= (\Diamond A \rightarrow \Diamond B) \rightarrow \Diamond (A\rightarrow B) \\ \\ C^* &= \neg(\Diamond A \rightarrow \Diamond B)^* \land (\Diamond(A \rightarrow B))^* \\ &= \neg(\neg (\Diamond A)^*\land(\Diamond B)^*)\land \Box(A \rightarrow B)^* \\ &= \neg(\neg \Box A^* \land \Box B^*) \land \Box(\neg A^* \land B^*) \\ &= (\Box A^* \lor \neg \Box B^*) \land \Box\neg(A^* \lor \neg B^*) \\ \\ \neg C^* &= \neg(\Box A^* \lor \neg \Box B^*) \lor \neg\Box(\neg A^* \land B^*) \\ &= \neg(\Box B^* \rightarrow \Box A^*) \lor \neg\Box(\neg A^* \land B^*) \\ &= (\Box B^* \rightarrow \Box A^*) \rightarrow \neg\Box(\neg A^* \land B^*) \end{aligned}
    C C ¬ C = ( A B ) ( A B ) = ¬ ( A B ) ( ( A B ) ) = ¬ ( ¬ ( A ) ( B ) ) ( A B ) = ¬ ( ¬ A B ) ( ¬ A B ) = ( A ¬ B ) ¬ ( A ¬ B ) = ¬ ( A ¬ B ) ¬ ( ¬ A B ) = ¬ ( B A ) ¬ ( ¬ A B