Question

If x+y+z =1. then xy+yz+zx =-1and xyz=-1,then find the value of x^3+y^3+z^3

Answer 1

x+y+z =1. then xy+yz+zx =-1and xyz=-1 X^2+y^2+z^2==(x+y+z)^2-2 (xy+yz+zx) =1-2=-1 X^3+y^3+z^3=(x+y+z)(x^2+y^2+z^2-(xy+yz+zx)+3xyz =1×(-1+1)-3 =-3