directrix


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di·rec·trix

 (dĭ-rĕk′trĭks, dī-)
n. pl. di·rec·trix·es or di·rec·tri·ces (dī′rĕk-trī′sēz)
1. Mathematics A fixed curve traversed by a generatrix in generating a conic section or a cylinder.
2. The median line in the trajectory of fire of an artillery piece.

directrix

(dɪˈrɛktrɪks; daɪ-)
n
1. (Mathematics) geometry a fixed reference line, situated on the convex side of a conic section, that is used when defining or calculating its eccentricity
2. (Professions) a directress
[C17: New Latin, feminine of director]

di•rec•trix

(dɪˈrɛk trɪks, daɪ-)

n., pl. di•rec•trix•es, di•rec•tri•ces (dɪˈrɛk trɪˌsiz, daɪ-, ˌdaɪ rɛkˈtraɪ siz)
1. a fixed line used in the description of a curve or surface.
2. Archaic. directress.
[1695–1705]
usage: See -trix.

di·rec·trix

(dĭ-rĕk′trĭks)
A straight line used in constructing a curve such as a parabola.
References in periodicals archive ?
DirectriX was one of five teams that completed the Challenge.
Therefore, a suitable candidate for the focus is any point on the y-axis, F(0,k), and a suitable candidate for the directrix is any line that runs parallel to the x-axis, l: y = -k.
Because of the exclusive DirectriX detector technology, when the needle-based detector option is used, the system offers the potential for a significant patient dose reduction.
This condition is determined by the kinematic generation of the elongated directrix [D.
One line, at a multiple of six units from the centre (F) of the circles is darkened and represents the directrix (CD) of some conics, which can be plotted with a focus at F.
DX-S, Agra's new computed radiography (CR) solution, includes two unique technologies: DirectriX needle-based detector and Scanhead line-to-line CR stimulation and light collection.
Let F(0,p) by the focus of y = -p the directrix of the parabola [x.
A 21,000-square-foot building on the same property is leased long-term to Directrix.
Cohen currently sits on the board of three other public companies -- Cross Media Marketing (AMEX: XMM); Directrix (OTCBB:DRCX); and Greg Manning Auctions (Nasdaq: GMAI) -- as well as Interlink, a privately held magazine wholesale and distribution company.
In this way, the geometrical surfaces are generated by a generating curve G in it movement along the directrix curve D (Botez, 1967).
Draw a line perpendicular to the directrix through the point A; i.