If x ^ 2 + 2 (M + 3) x + m ^ 2 + 3 = 0 has two real roots a and B, what is the minimum value of (A-1) ^ 2 + (B-1) ^ 2?

If x ^ 2 + 2 (M + 3) x + m ^ 2 + 3 = 0 has two real roots a and B, what is the minimum value of (A-1) ^ 2 + (B-1) ^ 2?


The univariate quadratic equation x ^ 2 + 2 (M + 3) x + m ^ 2 + 3 = 0 has two real roots a, B then ⊿ = [2 (M + 3)] ^ 2-4 (m ^ 2 + 3) ≥ 0, the solution is m ≥ - 1. According to Weida theorem, a + B = - 2 (M + 3); a * b = m ^ 2 + 3 (A-1) ^ 2 + (B-1) ^ 2 = a ^ 2-2a + 1 + B ^ 2-2b + 1 = (a + b) ^ 2-2a * B-2 (a + b) + 2 = 4 (M + 3) ^ 2-2 (m ^ 2 + 3) + 4 (M + 3) +