`1+(sin(A-B))/(cos A cos B)+(sin(B-C))/(cos B cos C)+(sin(C-A))/(cos C cos A)`

Prove that: ("sin"(A-B))/(cos A cosB)+(sin(B-C))/(cos B cos C)+("sin"(C-A))/(cos C cos A)=0

Prove that (sin(B-C))/(cos B cos C)+(sin(C-A))/(cos C cos A)+(sin(A-B))/(cos A cos B)=0

Prove that (sin(B-C))/(cos B cos C)+(sin(C-A))/(cos C cos A)+(sin(A-B))/(cos A cos B)=0

Prove that : (sin A - sin B)/ (cos A + cos B) + (cos A - cos B)/ (sin A + sin B) = 0

In any DeltaABC , prove that : (cos A)/(b cos C + c cos B) + (cos B)/(c cos A + a cos C) + (cos C)/(a cos B + b cos A) = (a^2 + b^2 + c^2)/(2abc)

If A and B are complementary angles, prove that : (sin A + sin B)/ (sin A - sin B) + (cos B - cos A)/ (cos B + cos A) = (2)/(2 sin^(2) A - 1)

In Delta ABC, (sin A (a - b cos C))/(sin C (c -b cos A))=

Prove that : (sin 2A+sin 2B + sin 2C)/(cos A + cos B + cos C-1) = 8 cos(A/2) cos( B/2) cos( C/2)

|(1,cos(A-B), cos(A-C)),(cos(B-A), 1, cos(B-C)),(cos(C-A), cos(C-B), 1)| (A) 0 (B) 1 (C) cosAcosBcosC (D) none of these

In any triangle ABC, if (cos A + 2 cos C)/(cos A + 2 cos B) = (sin B)/(sin C) then prove that, the triangle is either isosceles or right angled.