" 5."2(bc cos A+ca cos B+ab cos C)=(a^(2)+b^(2)+c^(2))

Prove that in a triangle ABC, bc cos A + ca cos B +ab cos C= 1/2(a^2+b^2+c^2)

In any ABC, prove that: 2(bosA+ca cos B+ab cos C)=a^(2)+b^(2)+c^(2)

In triangle ABC , prove that 2(bc cos A +ac cos B +ab cos C)=a^2+b&2+c^2 .

In any ABC,2(bc cos A+ca cos B+ab cos C)=

Prove in any triangle ABC that (i) a^(2)+b^(2)+c^(2)=2(bc cos A +ca cos B+ ab cos C) (ii) (b+c) cos A+(c+a)cos B+(a+b) cos C = a+b+c .

In any DeltaABC , 2 (bc cos A + ca cos B + ab cos C) =

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

In Delta ABC, if (2 cos A)/a+ (cos B)/b+ (2 cos C)/c=a/(bc)+b/(ca) , then A=