Question

x+y+z=3,x2+y2+z2=29,x3+y3+z3=45,求xyz和x4+y4+z4的值

Answer 1

x^4 + y^4 + z^4 = (x^2 + y^2 + z^2)^2 - 2(x^2y^2 + y^2z^2 + z^2x^2)

let (x^2y^2 + y^2z^2 + z^2x^2) = pp

pp = (xy + yz + zx)^2 - 2(xy^2z + yz^2x+zx^2y)

= (xy + yz + zx)^2 - 2xy...