" 12."x^(2)+y^(2)+2(xy-yz-zx)

Factorise : x^(2)+y^(2)+z^(2)-xy-yz-zx

If x=997 , y=998 z=999 then the value of x^(2)+y^(2)+z^(2)-xy-yz-zx will be

If x^(2) + y^(2) + z^(2) - xy- yz - zx = 0 , prove that : x= y = z

If ax+cy+bz=X, cx+by+az=Y, bx+ay+cz=Z, show that (a^(2)+b^(2)+c^(2)-bc-ca-ab)(x^(2)+y^(2)+z^(2)-yz-zx-xy)=X^(2)+Y^(2)+Z^(2)-YZ-ZX-XY

x+y-z=5 and x^(2)+y^(2)+z^(2)=29, find xy-yz-zx

Factorise : 4x^(2) + 9y^(2) + z^(2) + 12xy - 6yz - 4zx

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