In geometry, a pencil is a family of geometric objects with a common property, for example the set of lines that pass through a given point in a plane...

refer to: Pencil (film), a 2016 Tamil film Pencil (optics), a beam of radiant energy in the form of a narrow cone or cylinder Pencil (geometry), a family...

In geometry, Apollonian circles are two families (pencils) of circles such that every circle in the first family intersects every circle in the second...

In mathematics, a Lefschetz pencil is a construction in algebraic geometry considered by Solomon Lefschetz, used to analyse the algebraic topology of an...

all lines through a point is called a pencil, and their common intersection is called the vertex of the pencil. In any affine space (including a Euclidean...

In geometry, inversive geometry is the study of inversion, a transformation of the Euclidean plane that maps circles or lines to other circles or lines...

Donaldson, Simon K.; Katzarkov, Ludmil (2005). "Singular Lefschetz pencils". Geometry & Topology. 9 (2): 1043–1114. arXiv:math/0410332. doi:10.2140/gt.2005...

the spheres of the pencil are planes, otherwise there is only one plane (the radical plane) in the pencil. In their book Geometry and the Imagination...

anchoring, and the other leg holds a drawing tool, such as a pencil, a short length of just pencil lead or sometimes a pen. The handle, a small knurled rod...

In geometry, an incidence relation is a heterogeneous relation that captures the idea being expressed when phrases such as "a point lies on a line" or...

affine geometries and Euclidean geometry is a special instance of this type of geometry. In some other geometries, such as hyperbolic geometry, lines...

the whole cone) has a circular symmetry. In common usage in elementary geometry, cones are assumed to be right circular, where circular means that the...

dual transformation, taking all the lines through a point (a pencil) to another pencil by means of an axis of perspectivity is called an axial perspectivity...

algebraic geometry, Chasles' theorem says that if two pencils of curves have no curves in common, then the intersections of those curves form another pencil of...

type of conic is determined by the value of the eccentricity. In analytic geometry, a conic may be defined as a plane algebraic curve of degree 2; that is...

mathematics and geometry lessons. It includes two set squares, a 180° protractor, a 15 cm ruler, a metal compass, a metal divider, a 9 cm pencil, a pencil sharpener...

In geometry, the elongated square bipyramid (or elongated octahedron) is the polyhedron constructed by attaching two equilateral square pyramids onto a...

In geometry, two or more objects are said to be concentric when they share the same center. Any pair of (possibly unalike) objects with well-defined centers...

theory Lefschetz pencil bundle of principal parts Grothendieck, Alexandre; Dieudonné, Jean. EGA IV, 21.3. Hartshorne, R. 'Algebraic Geometry', proposition...

A carpenter pencil (carpentry pencil, carpenter's pencil) is a pencil that has a body with a rectangular or elliptical cross-section to allow it to be...

from the pencil definition, together with the fact that every pencil has a unique orthogonal pencil; see Schwerdtfeger, Hans (1979), Geometry of Complex...

launched the "Multipen", a mechanical pencil that allowed the variation of colors, with four of them contained on each pencil. Although stylographs never overtook...

A linear space is a basic structure in incidence geometry. A linear space consists of a set of elements called points, and a set of elements called lines...

plane (including the Euclidean plane), there is one ideal point for each pencil of parallel lines of the plane. Adjoining these points produces a projective...

notebooks category. Subsequently, Classmate added pens, pencils, mechanical pencils and geometry boxes to its portfolio. It uses eco-friendly and elemental...

and geometry. The Hessian matrix, the Hesse normal form, the Hesse configuration, the Hessian group, Hessian pairs, Hesse's theorem, Hesse pencil, and...

Geometry of Complex Numbers is an undergraduate textbook on geometry, whose topics include circles, the complex plane, inversive geometry, and non-Euclidean...

In geometry, the hexagonal prism is a prism with hexagonal base. Prisms are polyhedrons; this polyhedron has 8 faces, 18 edges, and 12 vertices. Since...

The Pencil Code is a high-order finite-difference code for solving partial differential equations, written in Fortran 95. The code is designed for efficient...

In projective geometry, duality or plane duality is a formalization of the striking symmetry of the roles played by points and lines in the definitions...