Question

Using the Euclidean Algorithm or the Extended Euclidean Algorithm, compute d=gcd(42042,1071). Certify that your value of d is correct by showing that the conditions of the GCD Characterization Theorem are satisfied.

Answer 1

here an example on that.
http://en.wikipedia.org/wiki/Euclidean_algorithm#Concrete_example

Answer 2

http://www.wolframalpha.com/input/?i=gcd%2842042%2C1071%29