Puas yog lub khob hliav qab polyhedron piav qhia koj paub li cas?
Puas yog lub khob hliav qab polyhedron piav qhia koj paub li cas?

Video: Puas yog lub khob hliav qab polyhedron piav qhia koj paub li cas?

Video: Puas yog lub khob hliav qab polyhedron piav qhia koj paub li cas?
Video: Muaj Yis hauv Xib tes yuav Qhia tau Txoj Hmoo li cas 2024, Hlis ntuj nqeg
Anonim

Lub tog raj kheej, cones , thiab spheres tsis yog polyhedrons , vim lawv muaj nkhaus, tsis tiaj tus, nto. A lub tog raj kheej muaj ob qho tib si, congruent puag uas yog lub voj voog. A khob khob muaj ib puag ncig puag ncig thiab vertex uas tsis nyob ntawm tus puag. Lub sphere yog ib daim duab qhov chaw uas muaj tag nrho nws cov ntsiab lus sib npaug ntawm qhov deb tus center point.

Tsis tas li ntawd, lub khob hliav qab puas yog polyhedron?

Lub ntsej muag ntawm lub polygon yog hu ua "polygons" vim hais tias lawv muaj ob sab ncaj. Nws yog paub tias lub polyhedron yog bounded los ntawm "txoj kab" thiab vim "kov nto" ntawm a khob khob . Cov khoom uas muaj lub hauv paus zoo li lub voj voog thiab nkhaus nto nrog ib qho vertex yog hu ua khob khob.

Tom qab ntawd, lo lus nug yog, dab tsi yog polyhedron? Hauv geometry, a polyhedron Nws tsuas yog three-dimensional khoom uas muaj cov sau ntawm polygons, feem ntau koom nrog lawv cov npoo. Lo lus muab los ntawm Greek poly (ntau) ntxiv rau Indo-European hedron (lub rooj). Lub plural ntawm polyhedron yog " polyhedra "(los yog qee zaum" polyhedrons ").

Kuj paub, ua li cas koj paub yog tias ib yam dab tsi yog polyhedron?

Kev txheeb xyuas tus yam ntxwv Lawv tsis muaj ntsej muag nkhaus. Lo lus 'ntsej muag' hais txog ob sab ntawm cov khoom. Yog li yog tag nrho cov sab ntawm lub solidare tiaj tus, ces nws yog a polyhedron . Tab sis yog lub solidhas tej nkhaus sab ntawm tag nrho cov, ces nws tsis yog ib polyhedron.

Vim li cas Cone tsis yog polyhedron?

Yog li lub tog raj kheej yog tsis yog polyhedron rau ntau yam: nws lateral nto yog tsis yog dav hlau, nws lub hauv paus yog tsis yog polygons, thaum kawg nws muaj tsis muaj ua vertex! Tsis muaj ntsej muag, tsis muaj ntug, tsis muaj vertices, nws tsis tuaj yeem ua phem!

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