If ` sin theta + sin phi = 1/2` and `cos theta + cos phi = 1`then find the value of ` cot ((theta + phi) /2)`

If sin theta sin phi - cos theta cos phi+1 =0 then the value of 1+ cot theta tan phi is-

If sin theta+sin phi=a and cos theta+cos phi=b find the value of tan((theta-phi)/(2))

If sin theta+ sin phi = a, cos theta + cos phi = b, find the value of sin ( theta+phi) and cos 2theta + cos 2phi where |b|>|a|

If sin theta+ sin phi= a and cos theta+ cos phi= b , find : sin (theta+ phi) .

If sin theta+ sin phi= a and cos theta+ cos phi= b , find : cos (theta+ phi) .

If sin theta+ sin phi= a and cos theta+ cos phi= b , find : 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 sin 2 theta + sin 2 phi =1/2 and cos 2 theta + cos 2 phi =3/2, then cos ^(2) (theta - phi)=

If sin 2 theta + sin 2 phi =1/2 and cos 2 theta + cos 2 phi =3/2, then cos ^(2) (theta - phi)=

If tan theta = 1 and sin phi = (1)/(sqrt(2)), and theta, phi in[0,pi/2] , then the value of cos (theta + phi) is