Set Theory Logic: Finding True Statements in a Given Domain

AI Thread Summary
To determine when P(x) → Q(x) is true, it is essential to analyze the conditions of the open sentences P(x) and Q(x) within the domain S. P(x) is true for x in the interval [-1, 2], while Q(x) holds for x values where x² ≤ 2. Given S = [-1, 1], P(x) is true for all x in this domain, making it necessary to evaluate Q(x) for the same values. The discussion raises the question of whether proving P(x) false leads to a vacuously true statement, emphasizing the importance of understanding the implications of truth values in logical statements. Ultimately, the focus is on identifying the specific x values in S that satisfy the truth of P(x) → Q(x).
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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?
 
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Would this mean that the statement is true vacuously?
 
Is there any ##x \in S## such that P(x) is false?
 
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