Symbolizing Quantified Statements in Logic

  • Context: Undergrad 
  • Thread starter Thread starter nicnicman
  • Start date Start date
Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
4 replies · 2K views
nicnicman
Messages
132
Reaction score
0
For a homework assignment I got the following as a question:

Symbolize the following using quantifiers, predicates and logical connectives.

For all integers n, 2n+1 is an odd integer.

Here is what I came up with:

O(x): x is odd
∀x((2x + 1) → O(x))

Would this be the correct form?

Thanks
 
Physics news on Phys.org
What I posted doesn't seem right. Maybe it should be something like this:

O(x): x is odd
∀xO(2x + 1)

Would this be correct?
 
Also, the domain of x would be all integers.
 
nicnicman said:
For a homework assignment I got the following as a question:

Symbolize the following using quantifiers, predicates and logical connectives.

For all integers n, 2n+1 is an odd integer.

Here is what I came up with:

O(x): x is odd
∀x((2x + 1) → O(x))

Would this be the correct form?

Thanks

Your transcription says that for all x, if 2x+1, then x is odd. I would use:

Domain is integers, as you said.
O(x): x is odd
∀x∀y((y=2x + 1) → O(y))
 
Yeah, that makes more sense. Now it's saying for every integer x, if y = 2x + 1, then y is always odd.

Thanks a lot!