Example. $\mathbb{Q}\left( \sqrt{ 2 }, \sqrt{ 3 } \right)$ [2305B]
Example. $\mathbb{Q}\left( \sqrt{ 2 }, \sqrt{ 3 } \right)$ [2305B]
(D&F p.576) Since every subgroup of the Klein-4 group is normal, all the subfields of $\mathbb{Q}(\sqrt{ 2 }, \sqrt{ 3 })$ are Galois extensions of $\mathbb{Q}$.