a. -16
b. -8
c. -2
d. -1
dengan cara
Jika x₁ dan x₂ adalah akar persamaan 2x² + x – 8 = 0, maka 2x₁ + 2x₂ adalah…
Jawaban Terkonfirmasi
2x² + x – 8 = 0
x₁ + x₂ = -b/a
= -1/2
2x₁ + 2x₂ = 2 (x₁ + x₂)
= 2 × -1/2
= -1
x₁ · x₂ = c/a
= -8/2
= -4
2x₁ · 2x₂ = 2 (x₁.x₂)
= 2 (-4)
= -8
X1 + x2 = -b/a = -1/2
2×1+2×2 = 2(x1+x2) = 2 (-1/2) = -1