Cambridge EXT 2 - Chapter 2 | Q+As (1 Viewer)

[ISAM77]

Hi guys, I have a question from this chapter (Proof). Please help, if you can. And if you have questions of your own from this chapter of the cambridge book, pls post them here and I'll try help as well.

2A Q13.
Following directly the explanation of the question, it is clear that we have a), c), and d) are True. And b) is False. As confirmed by the answers.

However, I'm not sure I understand the point of this question, nor the logic behind why c) is True? (besides the circular argument of it being true because it satisfies the definition of an implication as given in the question).

 

[Drongoski]

If p implies q, then consider the truth table of p => q:

p q | p=>q
______________________
T T | T
T F | F
F T | T
F F | T

Out of the 4 p:q possibilities, only the T:F case is F(False)
In this question, we have p:q as follows: a) F:T b) T:F c) F:F d) T:T
So only b) is False.