The problem states:

Determine Q(D) for D = {m + n√2 | m,n inZ} where D is an intefral domain and Q(D) its quotient field.

I know that the answer is Q(D) http://upload.wikimedia.org/math/3/f...a5218d6a7b.pngQ(√2), but am not sure how to come to this conclusion.