Im from abroad, can somebody please help me prove this GCD problem
Your attachment says (a/(a, b), b/(a,b)). Since this is titled "GCD problem" I presume that (x, y) here means the greatest common divisor of a and b. Let x be the GCD of a and b. Then a= cx and b= dx for some integers c and d are integers that have no factors in common (If c= pq and d= pr then a= pqx and b= prx so that the greatest common divisor is px, not x). So a/(a,b)= c and b/(a,b)= d and, since they have no common divisors, (a/(a,b), b/(a,b)) is 1.