Question

Persamaan matriks di lampiran mempunyai dua akar positif x₁ dan x₂.Apabila x₁=4x₂ maka nilai p=...

Answer 1

berarti kan =

[2+px, 1 + 2x] [1,x] = 0

[2+px + x + 2x²] = 0

2x² + (p+1)x+ 2 = 0

x1 .x2 = 1

4x2.x2 = 1

4x2² = 1

x2² = 1/4

x2 = 1/2

x1 = 4(1/2) = 2

jadi :

x1 + x2 = (-p-1)/2

2 + 1/2 = (-p-1)/2

5/2 = (-p-1)/2

-p-1 = 5

-p = 4

p = -4