Question

If x+y+z = 1 , xy + yz + zx = -1 and xyz = -1, then find the value of x³+y³+z³

Answer 1

x^3+y^3+z^3 = (x+y+z)^3 +3xyz - 3(x+y+z)(xy+yz+zx)
=> x^3+y^3+z^3 = (1)^3 + 3 (-1) - 3 (1) (-1) = 1