EXAMPLE1 推理与证明方法 Hypotheses:PVQ,P→R,Q→S Conclusion:S∨R Proof: PVQ,P→R,Q→S→S∨R 2/24/202111:15PM Deren Chen Zhejiang univ推理与证明方法 2/24/2021 11:15 PM Deren Chen, Zhejiang Univ. 5 EXAMPLE 1 Hypotheses: P ∨ Q, P → R, Q → S Conclusion: S ∨ R Proof: P ∨ Q, P → R, Q → S  S ∨ R