14. y = x² - 5x + p melalui (-1,2p)
2p = 1 + 5 + p
p = 6
y = x² - 5x + 6
tipot sumbu X (3,0) dan (2,0)
= x1².x2 + y1².y2 + x1.x2² + x1.x2²
= (3)².2 + 0².0 + 3.(2)² + 3.(2)²
= 18 + 12 + 12
= 18 + 14
= 32 Jawaban C.
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15. x² + ax + 1 - a = 0
x1 + x2 = -b/a = -a/1
x1.x2 = c/a = 1 - a/1
1/x1 + 1/x2 = 4/3
x1 + x2/x1.x2 = 4/3
-a/1 : 1 - a/1 = 4/3
-a/1 × 1/1 - a = 4/3
-a/1 - a = 4/3
4 - 4a = -3a
-4a + 3a = -4
-a = -4
a = 1
nilai dari (a - 2)(a - 3)
= (1 -2)(1 - 3)
= -1 . -2
= 2 Jawaban E.
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16. f(x) = ax² + bx + c mempunyai titik puncak (1,3)
dan sumbu x negatif
maka, a > 0, b > 0, c > 0 Jawaban A.
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17. x² - 6x + 2 = 0
a + b = 6
a.b = 2
persamaan kuadrat yang akar akarnya (1/a + 1/b)^ab dan (ab)^1/a + 1/b
a + b = (1/a + 1/b)^ab + (ab)^1/a + 1/b
a + b = (a + b/a.b)^ab + (ab)^a + b/a.b
a + b = (6/2)² + (2)^6/2
a + b = 3² + 2³
a + b = 9 + 8
a + b = 17
a.b = (1/a + 1/b)^ab . (ab)^1/a + 1/b
a.b = (6/2)² . (2)^6/2
a.b = 3² . 2³
a.b = 9 . 8
a.b = 72
x² - 17x + 72 = 0 Jawaban A.
