tangency
21Circle packing theorem — Example of the circle packing theorem on K5, the complete graph on five vertices, minus one edge. The circle packing theorem (also known as the Koebe–Andreev–Thurston theorem) describes the possible tangency relations between circles in the plane …
22Contract curve — Blue contract curve showing points of tangency of indifference curves in an Edgeworth box In microeconomics, the contract curve is the set of points, representing final allocations of two goods between two people, that could occur as a result of… …
23Steiner chain — In geometry, a Steiner chain is a set of n circles, all of which are tangent to two given non intersecting circles (blue and red in Figure 1), where n is finite and each circle in the chain is tangent to the previous and next circles in the chain …
24Analytic geometry — Cartesian coordinates. Analytic geometry, or analytical geometry has two different meanings in mathematics. The modern and advanced meaning refers to the geometry of analytic varieties. This article focuses on the classical and elementary meaning …
25Hyperbola — This article is about a geometrical curve, a conic section. For the term used in rhetoric, see Hyperbole …
26Apollonius of Perga — Apollonius of Perga. Apollonius of Perga [Pergaeus] (Ancient Greek: Ἀπολλώνιος) (ca. 262 BC – ca. 190 BC) was a Greek geometer and astronomer noted for his writings on conic sections. His innovative methodology and terminology, especially in the… …
27Singular solution — A singular solution ys ( x ) of an ordinary differential equation is a solution that is tangent to every solution from the family of general solutions. By tangent we mean that there is a point x where ys ( x ) = yc ( x ) and y s ( x ) = y c ( x ) …
28Cissoid of Diocles — construction In geometry, the cissoid of Diocles is a cubic plane curve notable for the property that it can be used to construct two mean proportionals to a given ratio. In particular, it can be used to double a cube. It can be defined as the… …
29SolidWorks — The SolidWorks interface, showing feature based history dependent modeling …
30Malfatti circles — In geometry, the Malfatti circles are three circles inside a given triangle such that each circle is tangent to the other two and to two sides of the triangle. They are named after Gian Francesco Malfatti, who made early studies of the problem of …
