Yuav ua li cas ua ib tug conic seem ntawm parabola?
Yuav ua li cas ua ib tug conic seem ntawm parabola?

Video: Yuav ua li cas ua ib tug conic seem ntawm parabola?

Video: Yuav ua li cas ua ib tug conic seem ntawm parabola?
Video: Tsis Muaj Peev Xwm Yuav Ua Li Cas 2024, Kaum ib hlis
Anonim

Yog ib parabola muaj ib tug ntsug axis, tus qauv daim ntawv ntawm cov kab zauv ntawm lub parabola yog qhov no: (x - h)2 = 4p(y - k), qhov twg p≠ 0. Lub vertex ntawm no parabola yog ntawm (h, k). Kev tsom xam yog nyob ntawm (h, k + p). Cov directrix yog kab y = k - p.

Tib neeg kuj nug, puas yog parabola ib ntu conic?

Cov parabola yog lwm tus paub conic seem . Geometric txhais ntawm a parabola yog qhov chaw ntawm tag nrho cov ntsiab lus xws li tias lawv sib npaug ntawm qhov taw tes, hu ua kev tsom, thiab ib txoj kab ncaj nraim, hu ua directrix. Hauv lwm lo lus, eccentricity ntawm a parabola yog 1.

Tsis tas li ntawd, 4 hom conic seem yog dab tsi? Plaub ntu conic yog lub voj voog , ellipses, parabolas, thiab hyperbolas. Conic Sections tau kawm ntev heev. Kepler thawj zaug pom tias cov ntiaj chaw muaj elliptical orbits. Nyob ntawm lub zog ntawm lub cev orbiting, cov duab orbit uas yog ib qho ntawm plaub hom conic seem tuaj yeem ua tau.

Ib yam li ntawd, koj yuav ua li cas ua ib qho conic seem?

Conic ntu yog tsim los ntawm kev sib tshuam ntawm lub dav hlau nrog lub khob hliav qab. Yog hais tias lub dav hlau yog parallel mus rau lub axis ntawm kiv puag ncig (lub y -axis), ces tus conic seem yog hyperbola. Yog hais tias lub dav hlau yog parallel mus rau lub generating kab, lub conic seem yog parabola.

Tus qauv qauv ntawm parabola yog dab tsi?

f (x) = a(x - h)2 + k, qhov twg (h, k) yog lub vertex ntawm tus parabola . FYI: Cov phau ntawv sib txawv muaj kev txhais lus sib txawv ntawm kev siv " txheem daim ntawv Ib txhia hais tias f (x) = ax2 + bx + c yog " txheem daim ntawv ", thaum lwm tus hais tias f (x) = a(x - h)2 +k yog " txheem daim ntawv ".

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