If `(x)/(cos theta)=(y)/(cos(theta-(2pi)/(2)))=(2)/(cos(theta+(2pi)/(3))), then x+y+z=`

If (x)/(cos theta)=(y)/(cos(theta-(2pi)/(3)))=(z)/(cos(theta+(2pi)/(3))), then x+y+z=

If (x)/(cos theta)=(y)/(cos(theta-(2 pi)/(3)))=(z)/(cos(theta+(2 pi)/(3))) then x+y+z is (a)1(b)0(c)-1(d) none of these

If x/(costheta)=y/(cos(theta-(2pi)/3))=z/(cos(theta+(2pi)/3)) then x+y+z is

If (x)/( cos theta ) = (y) /( cos (theta - 2pi//3))=(z)/( cos ( theta + 2pi//3)) , then x+y+z=

If x/(costheta)=y/(cos(theta-(2pi)/3))=z/(cos(theta+(2pi)/3)) then x+y+z is (a)1 (b) 0 (c) -1 (d) none of these

If x*cos theta=y*cos(theta+(2 pi)/(3))=2*cos(theta+(4 pi)/(3)) then evaluate xy+yz+zx

If x cos theta=y cos(theta+(2 pi)/(3))=z cos(theta+(4 pi)/(3)), prove that xy+yz+zx=0