Prove that if: `(sin(x-alpha))/(sin(x-beta)) =a/b` and `cos(x-alpha)/(cos(x-beta)) =A/B`
and `a+b!=0` then `cos(alpha-beta) = (aA+bB)/(aB+bA)`

Let (sin(theta-alpha))/("sin"(theta-beta))=a/b a n d(cos(theta-alpha))/("cos"(theta-beta))=c /d t h e n(a c+b d)/(a d+b c)= (a) cos(alpha-beta) (b) sin(alpha-beta) sin(alpha+beta) (d) none of these

If sin alpha + sin beta = a and cos alpha + cos beta = b, prove that : cos (alpha-beta) = 1/2 (a^2 + b^2 -2)

If cos(alpha+beta)=0 then sin(alpha+2beta)=

If sin(theta+alpha)=a,cos^(2)(theta+beta)=b, then sin(alpha-beta)=

Evaluate: intdx/sqrt(sin(x+alpha)cos^3(x-beta))

If sin alpha+sin beta=a and cos alpha-cos beta=b then tan((alpha-beta)/2) is equal to-

Prove that: cos2alpha\ cos2beta+sin^2(alpha-beta)-sin^2(alpha+beta)=cos2(alpha+beta) .

If cos alpha+ cos beta =1/3 and sin alpha+sin beta=1/4 prove that cos[(alpha-beta)/2] =+-(5/24)

If sin alpha + sin beta=a and cos alpha+cosbeta=b then tan((alpha-beta)/2) is equal to

If cos(theta-alpha) = a and cos(theta-beta) = b then the value of sin^2(alpha-beta) + 2ab cos(alpha-beta)