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

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

In any triangle ABC, prove that following: a(cos B cos C+cos A)=b(cos C cos A+cos B)=c(cos A cos B+cos C)

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

a^(2)(cos^(2)B-cos^(2)C)+b^(2)(cos^(2)C-cos^(2)A)+c^(2)(cos^(2)A-cos^(2)B)=0

For any triangle ABC,prove that a(b cos C-c cos B)=b^(2)-c^(2)

For any triangle ABC, prove that (b+c)cos(B+C)/(2)=a cos(B-C)/(2)

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

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

In any triangle ABC, prove that following: quad a cos A=b cos B=c cos C=2b sin A sin C=2c sin A sin B