Which of the following arguments are not valid? (a) If Gora gets the job and works hard, then he will be promoted. If Gora gets promotion, then he will be happy. He will not be happy, therefore, either he will not get the job or he will not work hard . (b) Either Puneet is not guilty or Pankaj is telling the truth. Pankaj is not telling the truth, therefore, Puneet ... Suppose that n2>1, then n>1. Codes: (A) (a) and (c) (B) (b) and (c) (C) (a), (b) and (c) (D) (a) and (b)
Answer: B Explanation: (a) P: Gora gets the job Q: Gora works hard R: Gora gets promotion S: Gora will be happy The argument can bet written as (P˄Q)→R R→S ¬S ... also be written as: ((P˅Q)˄¬P)→Q where P, and Q are propositions expressed in some formal system.