[" 95.If "x,y" and "z" are real and distinct,then prove that "f(x,y)],[=x^(2)+4y^(2)+9z^(2)-6yz-3zx-2xy" is always non nega- "]

The range of x^(2)+4y^(2)+9z^(2)-6yz-3xz-2xy is

The range of x^(2)+4y^(2)+9z^(2) - 6yz-3xz-2xy is

If x,y and z are three different numbers, then prove that : x^(2) + y^(2) + z^(2)- xy - yz- zx is always positive

If x, y and z are real and distinct, then x^(2)+9y^(2)+16z^(2)-3xy-12yz-4zx is always

If x, y and z are real and distinct, then x^(2)+9y^(2)+16z^(2)-3xy-12yz-4zx is always

If x,y, and z are real and different and u=x^(2)+4y^(2)+9z^(2)-6yz-3zx-2xy, then u is always a.non-negative b.zero c.non-positive d.none of these

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

Find the product: (3x+2y+2z)(9x^(2)+4y^(2)+4z^(2)-6xy-4yz-6zx)

If x ,y and z are real and different and u=x^2+4y^2+9z^2-6y z-3z x-2x y ,then u is always (a). non-negative b. zero c. non-positive d. none of these