Truth values of nested quantifiers

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SUMMARY

The discussion centers on the truth value of the nested quantifiers in the expression ∃x∃xP(x,y), where P(x,y) is defined as 2x + y = 1 and the domain for x and y is the set of all integers. Participants clarify that the expression contains a typographical error, as using the same variable for both quantifiers is redundant. The correct formulation should be ∃x∃yP(x,y), allowing for distinct variables in the quantification. This distinction is crucial for accurately interpreting the logical statement.

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Homework Statement



Let P(x,y) denote the sentence 2x +y = 1
What is the truth value of ∃x∃xP(x,y) where the domain of x, y is the set of all integers.


Homework Equations





The Attempt at a Solution



This problem doesn't make sense to me. Doesn't one of the variables need to be a y in ∃x ∃xP(x,y)? In other words shouldn't the proposition be ∃x∃yP(x,y) or something similar?

Could this simply be a typo?

Thanks for any suggestions.
 
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It's a typo. Two quantifiers in a row on the same variable is the same as one. It's a bit like Porky Pig "There is a.. There is a... I say, there is an x..."
 

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