If `A+B+C=pi,` prove that `tan^2A/2+tan^2B/2+tan^2C/2geq1.`

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

If A + B + C = pi , prove that tan3A + tan3B + tan3C = tan3A*tan3B*tan3C

In DeltaABC , prove that: s^(2).tan(A/2)tan(B/2)tan(C/2)=Delta

If A+B+C=180^@, then prove that tan^2 (theta/2)=tan(B/2) tan(C/2). when cos theta(sin B+sin C)=sin A.

In DeltaABC , prove that: tan2A + tan2B+tan2C=tan2Atan2Btan2C

If A ,\ B ,\ C are the interior angles of a triangle A B C , prove that tan((C+A)/2)=cotB/2 (ii) sin((B+C)/2)=cosA/2

In DeltaABC , prove that: (a+b+c).(tan(A/2)+tan(B/2))=2c cot(C/2)

If the sides a,b,c are in A.P., prove that (tan)A/2+ (tan) c/2=2/3( cot) B/2.

if ABC is a triangle and tan(A/2), tan(B/2), tan(C/2) are in H.P. Then find the minimum value of cot(A/2)*cot(C/2)

If A + B = (pi)/(4) , then prove that (1 + tan A) (1 + tan B) = 2