Menene dala: ma'anar, abubuwa, iri, zaɓuɓɓukan sashe

A cikin wannan ɗaba'ar, za mu yi la'akari da ma'anar, manyan abubuwa, nau'o'in da kuma yiwuwar zaɓuɓɓuka don sashin dala. Bayanin da aka gabatar yana tare da zane-zane na gani don kyakkyawar fahimta.

Ma'anar Dala

dala adadi ne na geometric a sararin samaniya; polyhedron wanda ya ƙunshi tushe da fuskoki na gefe (tare da madaidaicin madaidaicin), adadin wanda ya dogara da adadin kusurwoyi na tushe.

lura: dala lamari ne na musamman.

abubuwan dala

Ga hoton da ke sama:

• Base (quadrangle ABCD) – fuskar siffa wacce ke da polyhedron. Ba ta mallaki saman ba.
• saman dala (ma'ana E) shine abin gama gari na dukkan fuskokin gefe.
• Fuskokin gefe triangles ne waɗanda ke haɗuwa a tsaye. A wajenmu, wannan shine: Babban Sharuɗɗan Saye, AED, BEC и CED.
• Haƙarƙari na gefe - bangarorin fuskokin gefe, ban da waɗanda ke cikin tushe. Wadancan. wannan shine AE, BE, CE и DE.
• Tsawon Pyramid (EF or h) – wani madaidaici ya fado daga saman dala zuwa gindinsa.
• Tsawon fuska (EM) - tsayin triangle, wanda shine gefen gefen adadi. A cikin dala na yau da kullun ana kiran su rashin gaskiya.
• Yankin saman dala shine yankin gindin da dukkan fuskokinsa na gefe. Formula don gano (daidaitaccen adadi), da dala, ana gabatar da su a cikin wallafe-wallafe daban-daban.

Ci gaban dala - adadi da aka samu ta hanyar "yanke" dala, watau lokacin da duk fuskokinsa suka daidaita a cikin jirgin daya daga cikinsu. Don dala na quadrangular na yau da kullun, haɓakawa a cikin jirgin saman tushe shine kamar haka.

lura: wanda aka gabatar a cikin wani littafin daban.

Ra'ayin sashe na dala

1. Sashin diagonal - Jirgin yankan yana wucewa ta saman adadi da diagonal na tushe. Dala mai kusurwa huɗu yana da irin waɗannan sassa guda biyu (ɗaya ga kowane diagonal):

2. Idan jirgin yankan ya yi daidai da gindin dala, sai ya raba shi gida biyu: dala mai kama da haka (ƙidaya daga sama) da dala da aka yanke (ƙidaya daga tushe). Sashen yana da tushe mai kama da polygon.

A cikin wannan hoton:

• pyramids Farashin EABCD и EA₁B₁C₁D₁ makamantan haka;
• hudu ABCD и A₁B₁C₁D₁ suna kuma kama.

lura: Akwai wasu nau'ikan yanke, amma ba su da yawa.

Nau'in pyramids

1. Dala na yau da kullun - tushe na adadi shine polygon na yau da kullum, kuma an ƙaddamar da ƙarshensa zuwa tsakiyar tushe. Yana iya zama triangular, quadrangular (hoton ƙasa), pentagonal, hexagonal, da dai sauransu.
2. Pyramid tare da gefen gefe daidai gwargwado zuwa tushe - daya daga cikin gefuna na gefen adadi yana samuwa a kusurwar dama zuwa jirgin saman tushe. A wannan yanayin, wannan gefen shine tsayin dala.
3. Truncated dala – bangaren dala da ke saura a tsakanin gindinsa da wani yanke jirgin sama daidai da wannan tushe.
4. Tetrahedron – Wannan dala ce mai siffar triangular, fuskokin da ke dauke da triangles guda 4, kowanne daga cikinsu ana iya daukarsa a matsayin tushe. Shin daidai (kamar yadda yake a cikin hoton da ke ƙasa) - idan duk gefuna daidai suke, watau duk fuskokin madaidaicin alwatika.