integers

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integers

by naaga » Thu Feb 12, 2009 7:20 am
If x and y are nonzero integers, is an integer?
(1) x is the product of 2 and some other integer.
(2) There is only one pair of positive integers whose product equals y.

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by DanaJ » Thu Feb 12, 2009 7:39 am
You missed smth here:
"If x and y are nonzero integers, is an integer?"
Is who an integer? I'll assume it's x/y. Don't consider my explanation if this is not the case.
1. if x is the product of 2 and some other integer, this makes x even. But since we do not know anything about y, then we can't tell if x/y is an integer.
2. actually leads us to believe that y is prime, since only prime numbers have exactly one pair of positive divisors, 1 and the number itself. Since we don't have any more info about x, then we can't solve this one.

Taking both equations together won't help, so my guess is E.