Tolong dijawab segera

Mapel : Matematika
Kelas : X SMA
Bab : Eksponen dan Persamaan Kuadrat

Pembahasan :
1.

[(3^1/2 - 5¯¹)/(5¯¹ - 3^1/2)]²
= [-(5¯¹ - 3^1/2)/(5¯¹ - 3^1/2)]²
= [-1]²
= 1

Jawaban : A

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2.

x² + (p - 4)x - p + 7 = 0

Akar tidak nyata
D < 0
b² - 4ac < 0
(P - 4)² - 4(1)(-p + 7) < 0
P² - 8p + 16 + 4p - 28 < 0
P² - 4p - 12 < 0
(P - 6)(p + 2) < 0
-2 < p < 6

Jawaban : D

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3.

2x² + qx + (q - 1) = 0

X1² X2 + X1 X2² = -5
X1 . X2(X1 + X2) = -5
(C/a)(-b/a) = -5
(q - 1)/2 (-q/2) = -5
(-q² + q)/4 = -5
-q² + q = -20
q² - q - 20 = 0
(q - 5)(q + 4) = 0
q = -4
q = 5

Jawaban : C