If $x+y+z=1, x y+y z+z x=x y z=-4$, then what is the value of $\left(x^3+y^3+z^3\right)$ ? |
8 -8 1 -1 |
1 |
Given, x + y + z = 1, xy + yz + zx = xyz = -4 We know that, x3 + y3 + z3 – 3xyz = (x + y + z) [(x + y + z)2 – 3(xy + yz + zx)] According to the question x3 + y3 + z3 – 3xyz = (x + y + z) [(x + y + z)2 – 3(xy + yz + zx)] x3 + y3 + z3 – 3(-4) = (1) [(1)2 – 3(-4)] x3 + y3 + z3 + 12 = (1 + 12) x3 + y3 + z3 + 12 = 13 x3 + y3 + z3 = (13 – 12) (x3 + y3 + z3 ) = 1 |