In any `DeltaABC`, prove that:` (a+b-c)/(a+b+c) = tan (A/2) tan (B/2)`

In any Delta ABC, prove that : ((a-b)/(c))=(tan((A)/(2))-tan((B)/(2)))/(tan((A)/(2))+tan((B)/(2)))

In any triangle ABC, prove that: (b-c)/(b+c)=(tan((b-C)/(2)))/(tan((B+C)/(2)))

In any DeltaABC , prove that ((b-c))/acosA/2=sin((B-C))/2

In any triangle ABC,prove that (a-b)/(a+b)=(tan((A-B)/(2)))/(tan((A+B)/(2)))

In DeltaABC , Prove that (s-a) tan (A/2)=(s-b) tan (B/2)=(s-c) tan (C/2)

In any triangle ABC, prove that following: (c)/(a-b)=(tan((A)/(2))+tan((B)/(2)))/(tan((A)/(2))-tan((B)/(2)))

In any DeltaABC , prove that a(bcosC-c cosB)=(b^(2)-c^(2))

In any DeltaABC , prove that ((a-b))/c"cos"C/2="sin"((A-B))/2

In any Delta ABC, prove that :1-tan((A)/(2))tan((B)/(2))=(2c)/(a+b+c)

In any triangle ABC, prove that following: (c)/(a+b)=(1-tan((A)/(2))tan((B)/(2)))/(1+tan((A)/(2))tan((B)/(2)))