Yog ib lub ellipse muaj qhov chaw (0, 0), eccentricity e thiab ib nrab loj axis a nyob rau hauv x-direction, ces nws foci nyob ntawm (±ae, 0) thiab nws cov directrices yog x=±a/e.
Dab tsi yog qhov taw qhia ntawm lub ntsej muag?
Mathwords: Directrices of an Ellipse. Ob kab sib npaug ntawm sab nraud ntawm ib qho ellipse perpendicular mus rau qhov loj axis. Directrics tuaj yeem siv los txheeb xyuas qhov ellipse.
Puas ellipses muaj Directrix?
directrix: Ib kab siv los tsim thiab txhais ib qho conic seem; ib tug parabola muaj ib tug directrix; ellipses thiab hyperbolas have two (plural: directrices).
Yuav ua li cas koj pom cov vertices ntawm ib tug ellipse?
txhawm rau nrhiav cov vertices hauv kab rov tav ellipse, siv (h ± a, v); txhawm rau nrhiav kev sib koom ua ke, siv (h, v ± b). Vertical ellipse muaj vertices ntawm (h, v ± a) thiab co-vertices ntawm (h ± b, v).
Koj pom qhov eccentricity ntawm lub ellipse li cas?
Kom nrhiav qhov eccentricity ntawm lub ellipse. Qhov no yog qhov pib muab raws li e=(1-b 2/a2)1/2. Nco ntsoov tias yog tias muaj cov ellipse nrog cov loj thiab me axes ntawm qhov sib npaug ntawm qhov ntev muaj qhov eccentricity ntawm 0 thiab yog li lub voj voog.
