(m) sin U Tas a + B +yoy. 17 85 amla tan'B + tany, at Rye

If (" cos " (A+B))/(" cos " (A-B)) =(" sin " (C+D))/(" sin " (C -D)) , prove that tan A tan B tan C + tan D=0

If cos(A+B) sin (C-D) = cos (A-B) sin (C+D) , then show that tan A tan B tan C + tan D =0

If cos(A+B) sin (C-D) = cos (A-B) sin (C+D) , then show that tan A tan B tan C + tan D =0

If sin A=a cos B and cos A=b sin B then tan^(2)B =

If tanx tany=a and x+y=2b show that tanx and tany are the roots of the equation z^2-(1-a)tan2b*z+a=0

If tanx tany=a and x+y=2b show that tanx and tany are the roots of the equation z^2-(1-a)tan2b*z+a=0

If cos A = tan B , cos B = tan C and cos C = tan A then show that sin A = sin B = sin C = 2sin 18^circ .

Prove that '(sin (x+y)) / (sin (x-y))=(tan x+tan y)/(tan x- ( tany ))'