Spatial geometry

The cross product of two vectors is important concept which is applied in solving many problems when using the spatial coordinate method. By applying the Theory of Didactical Situations in Mathematics, the authors designed teaching situation that they call “the cross product of two vectors concept” in which students learn through situations that involve action, communication and validation.

5p tamynhan8 04-11-2020 16 1   Download

The ripplon modes of two segregated Bose-Einstein condensates (BECs) confined by one and two hard walls are respectively studied by means of the hydrodynamic approach within the Gross-Pitaevskii (GP) theory. For the system at rest we find that due to the spatial restriction the dispersion relations are of the form ω ∼ k 2 in low momentum limit for both cases, while for the system in motion parallel to the interface the dispersion relations for both cases are ω ∼ k at low momentum limit and, furthermore, the system becomes unstable.

8p thuyliebe 08-10-2018 26 0   Download

In 1991, David Gale and Raphael Robinson, building on explorations carried out by Michael Somos in the 1980s, introduced a three-parameter family of rational recurrence relations, each of which (with suitable initial conditions) appeared to give rise to a sequence of integers, even though a priori the recurrence might produce non-integral rational numbers. Throughout the '90s, proofs of integrality were known only for individual special cases. In the early '00s, Sergey Fomin and Andrei Zelevinsky proved Gale and Robinson's integrality conjecture.

37p thulanh8 19-09-2011 57 14   Download

Purpose: To understand the importance of working together. Time: 45 minutes Materials: Six envelopes labeled A, B, C, D, E, and F. In each envelope is a square cut into 5 pieces- use hard cardboard to cut the patterns. Note: This is for a class size of 30 students. If you have over 40 students, increase the number of squares or cut pieces per square.

20p vantrungtran 01-02-2010 136 17   Download