" 31.If "sin theta+sin phi=a,cos theta+cos phi=b" then prove that "tan(theta-phi)/(2)=+-sqrt((4-a^(2)-b^(2))/(a^(2)+b^(2)))

If sin theta + sin phi = a, cos theta + cos phi = b prove that tan ((theta-phi)/2 )=pm sqrt((4-a^(2)-b^(2))/(a^(2)+b^(2)))

sin theta + sin phi = a, cos theta + cos phi = b then prove tan [(theta-phi) / (2)] = + - sqrt ((4-a ^ (2) -b ^ (2)) / (a ^ (2) + b ^ (2)))

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

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

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 : sin (theta+ phi) .

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

If sin 2theta+sin 2phi=1//2 and cos2theta+cos 2phi=3//2 , then cos^(2)(theta-phi)=

If sin 2theta+sin 2phi=1//2 and cos2theta+cos 2phi=3//2 , then cos^(2)(theta-phi)=