Search Results for ""

Since |(a+ib)(c+id)| = |a+ib||c+di| (1) |(ac-bd)+i(bc+ad)| = sqrt(a^2+b^2)sqrt(c^2+d^2), (2) it follows that (a^2+b^2)(c^2+d^2) = (ac-bd)^2+(bc+ad)^2 (3) = e^2+f^2. (4) This ...

Two geometric figures are said to exhibit geometric congruence (or "be geometrically congruent") iff one can be transformed into the other by an isometry (Coxeter and ...

Regardless of where one white and one black square are deleted from an ordinary 8×8 chessboard, the reduced board can always be covered exactly with 31 dominoes (of dimension ...

The cube of a graph is defined as its third graph power.

The dual of the great truncated cuboctahedron U_(20) and Wenninger dual W_(93).

800 The dual of the great rhombidodecahedron U_(73) and Wenninger dual W_(109).

A dozen dozen, or the square number 144.

A n-gonal cupola adjoined to a 2n-gonal antiprism.

The largest unit fraction, 1/2. 1/2 is a rational number with terminating decimal expansion 0.5.

A polygonal number of the form n(5n-3)/2. The first few are 1, 7, 18, 34, 55, 81, 112, ... (OEIS A000566). The generating function for the heptagonal numbers is ...