The maximum value of `cos^(2)A+cos^(2)B-cos^(2)C,` is

In a triangle ABC the maximum value of (a cos^(2)A//2 +b cos^(2)B//2+cos^(2)C//2)/(a+b+c) is

If A+B+C=pi then the value of cos ^(2)A + cos ^(2) B+ cos ^(2)C is-

If ABCD is a cyclic quadrilateral, then the value of cos^(2)A-cos^(2)B-cos^(2)C+cos^(2)D is ______.

If A+C+B=180, then the value of (cos ^(2) A+ cos ^(2) B +cos ^(2) C-2 cos A cos B cos C) is-

In triangle ABC,/_C=(2 pi)/(3) then the value of cos^(2)A+cos^(2)B-cos A*cos B is equal

If A+B+C=(3pi)/(2) , prove that cos ^(2)A+ cos ^(2) B- cos ^(2)C=-2 cos A cos B sin C.

If A+ B + C = pi, then cos^(2) A + cos ^(2) B + cos ^(2) C is equal to : A) 1 - cos A cos B cos C B) 1 - 2 cos A cos B cos C C) 2 cos A cos B cos C D) 1 + cos A cos B cos C