Solution:
Given that, ABCD is a cyclic quadrilateral.
On adding Eqs. (i) and (ii), we get
cosA + cosB + cosC + cosD =0
lf A,B,C and D are the angles of a cyclic quadrilateral, then cos A + cos B + cos C + cos D is equal to
Given that, ABCD is a cyclic quadrilateral.
On adding Eqs. (i) and (ii), we get
cosA + cosB + cosC + cosD =0