求y＝x³-x²-x＋1的极值

求y＝x³-x²-x＋1的极值
求y＝x³-x²-x＋1的极值

求y＝x³-x²-x＋1的极值

y' = 3x² - 2x - 1 = (x - 1)(3x + 1) = 0

x = -1/3或x = 1

x < -1/3, y' > 0, 增

-1/3 < x < 1, y' < 0, 减

x > 1, y' > 0, 增

极大值: x = -1/3, y = 32/27

极小值: x = 1, y = 0