Interval nilai x agar grafik turun adalah …..
Jawaban:
f(x) = x³ + 3/2x² - 18x + 23
fungsi turun f'(x)<0
3x² + 3x - 18<0
3(x²+x-6) < 0
3(x-2(x+3) < 0
x < 2 V x 7 - 3
interval -3 < x < 2
[[ SN ]]
f(x) = x³ + (³/₂)x² - 18x + 23
f'(x) = 3x³⁻¹ + (³/₂)(2)x²⁻¹ - 18
f'(x) = 3x² + 3x - 18
Turun saat f'(x) < 0
3x² + 3x - 18 < 0
¹/₃(3x.....)(3x......) < 0
¹/₃(3x+9)(3x-6) < 0
(x+3)(x-2) < 0
-3 < x < 2
Jawaban b. -3 < x < 2
