If `a = cos theta + isin theta`, `b = cosphi + isinphi`, `c = cos psi + i sin psi` and `a/b+b/c+c/a=2` then `sin(theta-phi)+sin(phi-psi)+sin(psi-theta)` equals

If a cos theta - b sin theta =c, " then" a sin theta + b cos theta is equal to

cos 2 (theta+ phi) +4 cos (theta + phi ) sin theta sin phi + 2 sin ^(2) phi=

cos 2 (theta+ phi) +4 cos (theta + phi ) sin theta sin phi + 2 sin ^(2) phi=

If x=costheta+isintheta , y=cosphi+isinphi , z=cosPsi+isinPsi and (y)/(z)+(z)/(x)+(x)/(y)=1 , then : cos(phi-Psi)+cos(Psi-theta)+cos(theta-phi) is :

If x = cos theta cos phi + sin theta sin phi cos psi , y = cos theta sin phi - sin theta cos phi cos psi and z = sin theta sin psi , then x^(2) + y^(2) + z^(2) equals :

If x= cos theta+ I sin theta and y= cos psi + I sin psi , then show that (x)/(y)+(y)/(x)= 2 cos (theta- psi) .

If a=cos theta+i sin theta and b= cos phi + i sin phi then prove that a^3/b^3+b^3/a^3=2cos3(theta-phi)

If cos theta+cos phi=a and sin theta - sin phi=b , then: 2cos(theta + phi) =