Prove that `(b + c -a) (cot.(B)/(2) + cot.(C)/(2)) = 2a cot.(A)/(2)`

Prove that tan A - cot A =-2 cot2A

Prove that : (1 + cot A)^(2) + (1 - cot A)^(2) = 2 cosec^(2) A

In any DeltaABC , prove that cot (A/2) + cot (B/2) + cot (C/2) = (a+b+c)/(b+c-a) cot (A/2)

In any triangle , prove that ((b-c)/( b+c)) cot ""(A)/(2) +((b+c)/(b-c)) tan ""(A)/(2) = 2 cosec (B-C)

In any triangle ABC prove that cot(A/2)+cot(B/2)+cot(C/2)=cot(A/2)cot(B/2)cot(C/2)

Prove that: (cos A+cos B)/(cos B-cos A)=cot((A+B)/2)cot((A-B)/2)

Prove that : (cot A - 1)/ (2 - sec^(2) A) = (cot A)/ (1 + tan A)

In a triangle ABC, prove that (a) cos(A + B) + cos C = 0 (b) tan( (A+B)/2)= cot(C/ 2)

Prove that : cot^(2) A - cot^(2) B = (cos^(2) A - cos^(2) B)/ (sin^(2) A sin^(2) B) = cosec^(2) A - cosec^(2)B

If A+B+C=pi , prove that : cot, A/2+ cot, B/2 + cot, C/2 = cot, A/2 cot, B/2 cot, C/2