✨ 最佳解答 ✨ 綾 約2個月以前 f(1) = a + b + c = -2 f(-1) = 2a + b = -1 f(2) = 4a + b = 3 f(2) - f(-1) = 2a = 4 a = 2 b = -5 c = 1 f(3) = 9a + 3b + c = 18 - 15 + 1 = 4 留言