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

If ABCD is a cyclic quadrilateral, then the value of cos A - cos B + cos C - cos D =

If ABCD is a cyclic quadrilateral,then the value of cos A-cos B+cos C-cos D is

If ABCD is a cyclic quadrilateral then the value of cosA+cosB+cos C+cos D is

if ABCD is a cyclic quadrilateral, then find the value of cosA cosB - cos C cos D.

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

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

If ABCD is a cyclic quadrilateral, then the value of cosA-cosB+cosC-cosD is............... A) 0 B) 1 C) 2(cos B- cos D) D) 2 (cos A- cos C)

If ABCD is a cyclic quadrilateral, then cos A + cos B is equal to

If ABCD is a cyclic quadrilateral, then cos A+cos B is equal to

In a cyclic quadrilateral ABCD, the value of 2+sum cos A cos B, is