In any `DeltaABC`, prove that : `(b-c)/a cos^2 A/2 + (c-a)/b cos^2 B/2 + (a-b)/c cos^2 C/2 = 0`

In any Delta ABC, prove that: (b-c)/(a)cos^(2)((A)/(2))+(c-a)/(b)cos^(2)((B)/(2))+(a-b)/(c)cos^(2)((C)/(2))=0

In DeltaABC , prove that: a(cosC-cosB)=2(b-c)cos^(2)A/2

In any Delta ABC, prove that :a(b cos C-c cos B)=b^(2)-c^(2)

In any Delta ABC, prove that :a cos A+b cos B+c cos C=2a sin B sin C

In any DeltaABC , prove that 4(bc cos^(2)""A/2+ca cos^(2)""B/2+ab cos^(2)""C/2)=(a+b+c)^(2)

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

In any Delta ABC, prove that :(b^(2)-c^(2))cos2A+(c^(2)-a^(2))cos2B+(a^(2)-b^(2))cos2C=0

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