Set Theory Logic: Finding True Statements in a Given Domain

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
2 replies · 2K views
knowLittle
Messages
307
Reaction score
3

Homework Statement


In each of the two following open sentences P(x) and Q(x) over a domain S are given.
Determine all ##x \in S## for which P(x) → Q(x) is a true statement.

## P(x): x \in [-1, 2]; Q(x): x^{2} \leq 2; S=[-1,1] ##

Homework Equations


According to truth values for →:
a b a-> b
0 0 1
0 1 1
1 0 0
1 1 1

The Attempt at a Solution


If I can prove that P is False, then I will always get a T value for ->
Can I just say ## x \in [-1,1] ##, this would literally mean that statement P is false.
Could this count?
 
Physics news on Phys.org
Would this mean that the statement is true vacuously?