" D) "(mes)/(pi),(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))/(cos(A+B))+(cos(C+D))/(cos(C-D))=0, prove tht tan A tan B tan C tan D=-1

If ( cos (A+B))/( cos (A-B)) =( sin (C+D))/( sin (C -D)) then prove that tan A tan B tan C + tan D=0 ................. A) 0 B) -1 C) sqrt3 D) 1

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

(cos(A-B))/(cos(A+B))+cos(C+D)/(cos(C-D))=0 => tan A tan B tan C tan D =

If (cos (AB)) / (cos (A + B)) + (cos (C + D)) / (cos (CD)) = 0 Prove that tan A tan B tan C tan D = -1

(cos (AB)) / (cos (A + B)) + (cos (C + D)) / (cos (CD)) = 0rArr tan A tan B tan C tan D =

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 cos (A + B) sin (C- D) = cos (A- B) sin (C+D) , show that : tan A tan B tanC + tanD=0 .

If A+B+C= pi/2 , prove that tan A tan B+tan B tan C+tan C tan A=1