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mr_coffee
mr_coffee is offline
#1
Sep10-06, 08:52 PM
P: 1,629
Hello everyone!

I was wondering if someone could check to see if i did this problem correctly.

THe directions are the following: Fid the truth set of each predicate.
predicate: 1 <= x^2 <= 4, domain: Z. Where Z stands for integers and <= stands for less than or equal to.

The book did an example of the following:
predicate: 1 <= x^2 <= 4, domain: R.
There answer was:
The truth set is the set of all real numbers x, with the properlty that 1 <= x^2 <= 4, so the truth set is {x e R|-2 <= x <= -1 or 1 <= x <= 2 }. In other words, the truth set is the set of all real numbers between -2 and -1 inclusive and between 1 and 2 inclusive.


Now for my problem, wouldn't the answer be the exact same thing but instead write:
The truth set is the set of all real numbers x, with the properlty that 1 <= x^2 <= 4, so the truth set is {x e Z|-2 <= x <= -1 or 1 <= x <= 2 }. In other words, the truth set is the set of all integers between -2 and -1 inclusive and between 1 and 2 inclusive.

note: e stands for element of. I need to find the latex for all this so it will be clearer.

Whats the major difference between real numbers and integers anyways?

Thanks! :D
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