Definition. Let a, b Z. A positive whole number d is known as a typical divisor of an and b if d an and d b .

2. On the off chance that a number c is expressible in the structure c =ax by , it is notnecessary that c is the gcd(a, b). In any case, it follows from such a comparison, to the point that gcd(a, b) is a divisor of c. Why? . From the way that hatchet by=1 for a few whole numbers x and y we can suggest that an and b are moderately prime. Why?. Since hatchet by=1 is separable by gcd(a, b), that implies that gcd(a, b)=1. .