0710132人目の素数さん垢版 | 大砲2018/11/13(火) 07:25:20.32ID:UigxEbMv >>701 f(x) = x^3 -3AAx -B, とおくと f '(-A) = f '(A) = 0 さらに A = 1 +3t +3tt, B = ±(-2A+1)(A+3t+1)(A-3t-2) とおけば f(-2A+1) = f(A+3t+1) = f(A-3t-2) = 0, or f(2A-1) = f(-A-3t-1) = f(-A+3t+2) = 0,