[" If "ABCD" is a quadrilateral then "],[cos((A+B)/(2))+cos((C+D)/(2))=]

if ABCD0 is a quadrilatral then cos((A+B)/(2))+cos((C+D)/(2))=

If A,B,C,D are the angles of a quadrilateral then cos""((A+B)/(2))+ cos ""((C+D)/(2)) =

ABCD is a quadrilateral, then /_A+/_B+/_C+/_D=

If A,B,C,D are the successive angles of a cyclic quadrilateral, then- (i) cos((A+C)/2) + cos((B + D)/2) =

I: If A,B,C,D are angles of a cyclic quadrilateral then cos A + cos B + cos C + cos D=0 II : If A,B,C,D are the angles of a quadrilateral then cos""(A+B)/(2) + cos""(C+D)/(2) =0

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

If ABCD is a cyclic quadrilateral,the value of (tan(A)/(2)(tan)(C)/(2)+(tan)(B)/(2)(tan)(D)/(2) is

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

If ABCD is a cyclic quadrilateral then co (180^(@) +A) + cos (180^(@) - B) +cos(180^(@)-C) - sin (90^(@) - D)=