If `0 lt theta,philt pi` and `costheta + cosphi - cos (theta+phi)=3/2,` prove that `theta=phi = pi/3.`

If 0

If 0 lt theta , phi lt pi and 8 cos theta cos phi cos (theta + phi)+1=0 find theta and phi

If 3tan theta tan phi=1 then (cos(theta-phi))/(cos(theta+phi)) is

If sim 2theta+sin2phi=1/2 and cos 2theta+cos2phi=3/2 then cos^2(theta-phi)=

If 3tan theta tan phi=1. Prove that 2cos(theta+phi)=cos(theta-phi)

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

If 3 tan theta tan phi=1, then (cos (theta-phi))/(cos (theta+phi)) is

3tanthetatanphi=1 , then (cos(theta-phi))/(cos(theta+phi))=?

If 0 le theta lt pi/2 and costheta + sqrt(3) sin theta =2 , then what is the value of theta ?

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