Consider the vocabulary with only four propositions A,B,C and D. How many models are there for the following sentence ?
(⌐ A ∨ ⌐B ∨ ⌐C ∨ ⌐ D)
(A) 8
(B) 7
(C) 15
(D) 16
Answer: (C)
Explanation: There are four variables A, B, C, D. Therefore 2^4 = 16.
From 0 to 15 models are exist, but one is 0, so 15 is correct answer.
Quiz of this Question