Question

Ini soalnya bantu ya

Answer 1

Nomor 5
= x² - 5x - 7
x₁ + x₂ = -b/a
x₁ + x₂ = 5
x₁x₂ = c/a
x₁x₂ = -7
Maka :
(x₁² - 4x₁ + 3)(x₂² - 4x₂ + 3)
(x₁x₂)² - 4x₁x₂(x₁) + 3x₁² - 4x₁x₂(x₂) + 16x₁x₂ - 12x₁ + 3x₂² - 12x₂ + 9
(-7)² - 4(-7)(5) + 3(25 + 14) + 16(-7) - 12(5) + 9
49 + 140 + 117 - 112 - 60 + 9
143

Nomor 6
y = y
-2x + 3 = x² + (m - 1)x + 7
0 = x² + (m - 1 + 2)x + 7 - 3
0 = x² + (m + 1)x + 4
agar memiliki  penyelesaian :
D = 0
b² - 4ac = 0
(m + 1)² - 4(1)(4)  =  0
m² + 2m + 1 - 16 = 0
m² + 2m - 15 = 0
(m + 5)(m - 3) = 0
m = -5    dan    m = 3    [B.]