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Bab Stasioner
Matematika SMA Kelas XI

f(x) = x^3 - x² - 8x
f'(x) = 3 . x² - 2x - 8 = 0
(3x + 4) (x - 2) = 0
3x + 4 = 0
3x = -4
x = -4/3

atau

x - 2 = 0
x = 2

x = 2 atau x = -4/3

jawabannya A