The expression `cos^2 (phi+ b) + cos^2(phi+ a + b) + cos^2a-2 cosa cos(phi + b) cos (phi+ a + b)` is independent of

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 a sin phi+b cos phi=c then a cos phi-b sin phi is

If determinant |cos(theta+phi) sin(theta+phi)cos2phi sin thetacostheta sinphi costheta sintheta cosphi | is a. positive b. independent of theta c. independent of phi d. none of these

Prove that, cos^(2) (theta + phi) - sin^(2) (theta - phi) = cos 2 theta cos 2 phi

If a^(2)+b^(2)+c^(2)=1, then prove that a^(2)+(b^(2)+c^(2))cos phi,ab(1-cos phi),ac(1-cos phi)ba(1-cos phi),b^(2)+(c^(2)+a^(2))cos phi,bc(1-cos phi)ca(1-cos phi),cb(1-cos phi),c^(2)+(a^(2)+b^(2))cos phi is independent of a,b,c.

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 cos theta = (a cos phi + b) / (a + b cos phi) then (tan ((theta) / (2))) / (tan ((phi) / (2))) = (A) ( ab) / (a + b) (B) (a + b) / (ab) (C) sqrt ((a + b) / (ab)) (D) sqrt ((ab) / (a + b))