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calyne
(Discrete Structures) what does it mean for an integer to be "congruent mod 4" to 0, 2, 3 (for each)?
The simplest way to put it is that 2 integers are congruent mod 4 if they have the same remainder when you divide by 4. So 1 and 9 would be congruent mod 4, while 1 and 7 wouldnt be.
There is a little more to it than that, but this is the easiest way to put it.
what are three integers that are congruent mod 4 to 0 then?
m conguent to n mod k if (m-n) is a multiple of k
0's remainder when you divide by 4 is 0, so what other integers have a remainder of 0 when divided by 4?