Question

Jika x² + 4x - 5 = 0 maka persamaan kuadrat baru yang akar akarnya x₁ + 3 dan x₂ + 3 adalah ...

Answer 1

X^2 + 4x - 5 = 0
x1 + x2 = -b/a = -4
x1.x2 = c/a = -5
Misal p = x1 + 3 dan q = x2 + 3
p + q = x1 + 3 + x2 + 3 = x1 + x2 + 6 = -4 + 6 = 2
pq = (x1 + 3)(x2 + 3) = x1.x2 + 3(x1 + x2) + 9 = -5 + 3(-4) + 9 = -8
Persamaan kuadrat baru
x^2 - (p + q)x + pq = 0
x^2 - 2x - 8 = 0