Skip to content
Worked Examples · Example 3

Q.Construct the truth table for the statement pattern (p∧q)→∼p(p \wedge q) \rightarrow \sim p and hence state whether it is a tautology, a contradiction or a contingency.

Maharashtra MsbshseTextbookSubjectiveImportance★★★★★
23% · 9/40 Questions
✓ Free question

With two statements there are 22=42^2 = 4 rows. Build the intermediate columns p∧qp \wedge q and ∼p\sim p, then the conditional.

ppqqp∧qp \wedge q∼p\sim p(p∧q)→∼p(p \wedge q) \rightarrow \sim p
TTTFF
TFFFT
FTFTT
FFFTT

Reading the rows. Row 1: p∧q=Tp \wedge q = T and ∼p=F\sim p = F, so T→F=FT \rightarrow F = F. Rows 2-4: the antecedent p∧qp \wedge q is FF, and a conditional with a false antecedent is TT.

The final column is F,T,T,TF, T, T, T — it contains both TT and FF, so the pattern is a contingency.

Verification. The only way (p∧q)→∼p(p \wedge q) \rightarrow \sim p can be false is p∧qp \wedge q true (so p=Tp = T and q=Tq = T) with ∼p\sim p false (so p=Tp = T) — exactly row 1, and no other row. One false row rules out a tautology, and three true rows rule out a contradiction, confirming a contingency.

✓Final answer

The truth-table column is F,T,T,TF, T, T, T, so (p∧q)→∼p(p \wedge q) \rightarrow \sim p is a contingency.

Unlock everything free for 14 days

  • Full step-by-step solutions
  • Concept-first explanations
  • Methods, shortcuts & mistakes
  • PYQ mapping + timed mock tests

Full access for 14 days. No credit card required.