If `A, B, C, D` be the angles of acyclic quadrilateral, show that : `cosA +cosB+cosC+cosD=0`.

If A,B,C and D are the angles of cyclic quadrilateral, prove that: i) cosA + cosB+cosC+cosD ii) cos(180^(@)-A)+cos(180^(@)+B)+cos(180^(@)+C)-sin(90^(@))

In a cyclic quadrilateral ABCD, then find cosA+cosB+cosC+cosD=?

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

In any quadrilateral ABCD, show that: cosA cosB-cosC cosD="sin"A "sin"B-"sin"C "sin"D.

If ABCD is a cyclic quadrilateral, then the value of cosA-cosB+cosC-cosD is equal to

Let A,B,C,D be the angles of a quadrilateral . If they are concyc lic , then the value of cosA+cosB+cosC+cosD is

Let ABCD be a cyclic quadrilateral then Statement:1 sinA + sinB+ sinC + sinD=0 and Statement:2 cosA + cosB + cosC + cosD=0