In any triangle `ABC,1-tan(A/2)tan(B/2)=`

In any triangle ABC , (tan(A/2)-tan(B/2))/(tan(A/2)+tan(B/2)) is equal to

In any triangle ABC, if tan (A/2), tan (B/2), tan (C/2) are in A.P., prove that, cosA, cosB, cosC are also in A.P.

In Delta ABC,1-tan((A)/(2))tan((B)/(2))=

If in a triangle ABC , tan A/2 and tan B/2 are the roots of the equation 6x^(2)-5x+1=0 , then

Show that in any triangle ABC,(a+b+c)(tan((A)/(2))+tan((B)/(2)))=2c cot((C)/(2))

Show that in any triangle ABC, (a+b+c) (tan (A/2) + tan (B/2)) = 2c cot (C/2)

in triangle ABC,tan A+tan B+tan C=