Wrong answer to the mini question.
-
a=4
b=2
Then gcd(a, b)=2 and gcd(a, 2b)=4!!! -
@thoughtfulmongoose Let a=2x and b=2y, then the question is asking for the GCD of 2x and 4y. Obviously 2 is a common divisor, but we don't know if x has any more 2s in it. If x has one more factor of 2 and y has none then the greatest common divisor is 4. So the answer should be NEI(not enough info)