Define : +√-3. Show that (+i is algebraic = 4.8.] over Q. [Hint: Theorem Let T be a commutative ring, and let S be a su
Posted: Mon Jul 11, 2022 12:04 pm
Define : +√-3. Show that (+i is algebraic = 4.8.] over Q. [Hint: Theorem
Let T be a commutative ring, and let S be a subring of T. Then IT (S) is a subring of T. PROOF. Let p and q be elements in IT (S), and set A = {p, q}. Then, by Proposition 4.6, S[A] ≤ IT(S). Since p, q E S[A] and S[A] is a subring of T, p-q E S[A] and pq E S[A]. Thus, p-q IT(S) and pq € IT(S).