akar akar persamaan dari polinomial x^3+3x^2-x+m=0. adalah x1, x2, x3. jika x2=-2, nilai x1 dikali x3= ....?

jawab

x³ + 3x² - x + m = 0
x1 + x2 + x3 = -b/a = -3
x1x2 + x1x3+ x2 x3 = c/a = -1
x1 x2 x3  = - d/a = m

x2= 2
x1 + x2 + x3 = - 3
x1 + x3 = - 5

x1 x2 + x1 x3 + x2 x 3 = -1
x1 x2 + x2 x3 + x1  x3   = -1
x2(x1 + x3) + x1 x3  = -1
2(-5) + x1 x3 = -1
-10 + x1 x3 = - 1
x1. x3 = -1 + 10    
x1.x3 = 9