Question

Diket. Fungsi f(x) = x^3 - (m + 4)x^2 + (5m - 1)x + 4. Fungsi tersebut mencapai nilai balik maksimum untuk x = 2.

A. Tentukan nilai m !
B. Tentukan koordinat titik balik minimum!

Answer 1

F(x) = x³ - (m+4)x² + (5m -1)x + 4
f ' (x) =0
3x² - 2(m+4)x + (5m -1) = 0
x = 1 --> 3 - 2m -8 + 5m -1 = 0
3m - 6 = 0
m = 2

f(x) = x³ - (2+4)x² + (5.2 -1)x + 4
f(2) = 8 - (6)(4) + 9(2) + 4 
f(2) = 6
titik balik (x, f(x)) = (2, 6)