Question

`f(x)=3x^3-6x^2+9x+6` `f(x_1)=f(x_2)=f(x_3)=0` `x_1^2+x_2^2+x_3^2=?` result = 3 but how to find that ?

Answer 1

`"Result = -2, and not 3"`

Explanation:

`x_1^2+x_2^2+x_3^2 = (x_1+x_2+x_3)^2 - 2(x_1 x_2 + x_1 x_3 + x_2 x_3)`
`= (6/3)^2 - 2(9/3) = -2 " (Newton identities)"`