Mathematical Logic And Boolean Algebra Question 2

Question: Which of the following is false?

Options:

A) $ p\vee \tilde{\ }p $ is a tautology

B) $ \tilde{\ }(\tilde{\ }p)rightarrow p $ is a tautology

C) $ p\wedge \tilde{\ }p $ is a contradiction

D) $ ((p\wedge q)\to q)\to p $ is a tautology

Show Answer

Answer:

Correct Answer: D

Solution:

[d] The truth value of $ \tilde{\ }(\tilde{\ }p)rightarrow p $ as follow $ p $ $ \tilde{\ }p $ $ \tilde{\ }(\tilde{\ }p) $ $ \tilde{\ }(\tilde{\ }p)\to p $ $ p\to $ $ \tilde{\ }(\tilde{\ }p) $ $ \tilde{\ }(\tilde{\ }p) $ $ rightarrow p $ T F T T T T F T F T T T Since last column of above truth table contains only T Hence $ \tilde{\ }(\tilde{\ }p)\to p $ is a tautology.