In a triangle ABC, prove that for any angle `theta, b cos (A - theta) + a cos (B + theta) = C cos theta`.

In Delta ABC, b cos (C+ theta)+c cos (B- theta)=

If theta is any real number, then, in a triangle ABC, prove that a cos (B - theta) + b cos (A + theta) = c cos theta .

For any angle theta , costheta+cos(120^@+theta)+cos(120^@-theta)=........

In a triangle ABC, (c cos(A-theta) + acos (C + theta))/(b costheta) is equal to

In a triangle ABC, (c cos(A-theta) + acos (C + theta))/(b costheta) is equal to

If a cos theta - b sin theta = c then a sin theta + b cos theta=