14 . Nilai minimum fungsi kuadrat f(x) =2xpangkat2 - 8x + 10 adalah A.-2 B 2 C 34 D 18 15 .nilai maksimum yang di miliki fungsi kuadrat f(x) =30x - 5xpangkat2

Kelas 10 Matematika
Bab Persamaan dan Fungsi Kuadrat

14] f(x) = 2x² - 8x + 10
a = 2; b = -8; c = 10

sumbu simetri
= -b/2a
= - (-8)/2 . 2
= 2

f(2) = 2 . 2² - 8 . 2 + 10
f(2) = 2 . 4 - 16 + 10
f(2) = 8 - 16 + 10
f(2) = 2

15] f(x) = 30x - 5x²
a = -5; b = 30; c = 0

sumbu simetri
= -b/2a
= -30/(2 . (-5))
= 3

f(3) = 30 . 3 - 5 . 3²
f(3) = 90 - 5 . 9
f(3) = 90 - 45
f(3) = 45