GCD Basic Properties

 1. GCD is the largest positive integer(with one exception) that divides each of the integers in a given set.

2. Even if one or more input numbers are negative, output is always positive.

3. Both inputs/output are integers.

4. gcd(a,0) = |a|

5. gcd(0,0) = 0, this is defined like this. Though gcd(0,0) can be any integer. This is the only case where gcd is not positive. It is 0.

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