Cyclic quadrilateral (tangent of the acute angle between the diagonals)

Description

In Euclidean geometry, a cyclic quadrilateral or inscribed quadrilateral is a quadrilateral whose vertices all lie on a single circle. This circle is called the circumcircle or circumscribed circle, and the vertices are said to be concyclic. The tangent of the acute angle between the diagonals of the quadrilateral can be calculated by the sides and the semiperimeter of the quadrilateral.

Related formulas

Variables

θThe acute angle between the diagonals (degrees)
sSemiperimeter of the cyclic quadrilateral (m)
bLength of the side of the cyclic quadrilateral (BC) (m)
dLength of the side of the cyclic quadrilateral (DA) (m)
aLength of the side of the cyclic quadrilateral (AB) (m)
cLength of the side of the cyclic quadrilateral (CD) (m)