Mun lissafta yankin na akwatin

Na a jam'i na lissafi siffofi na daya daga cikin sauki za a iya ambata parallelepiped. Yana yana cikin siffar wani Prism wanda tushe ne parallelogram. Ba shi da wuya yin lissafi da yankin na akwatin, saboda da dabara ne mai sauqi qwarai.

Prism sa fuskokinku, vertices da gefuna. The rarraba wadannan bijiro da batun kafa abubuwa ne gamsu idan m adadin wanda wajibi ne ga samuwar na lissafi siffar. Parallelepiped ƙunshi 6 fuskoki, wanda suna da alaka da vertices 8 da kuma 12 hakarkarinsa. Kuma da daura da akwatin zai zama ko da yaushe daidaita. Saboda haka, zan samu akwatin yankin, shi ya ishe domin sanin girman ta fuskoki uku.

Parallelepiped (ajalin nufin "layi daya fuskoki" a Girkanci harshe) yana da wasu Properties wanda za a iya ambata. Na farko, da fasali na adadi aka tabbatar kawai a tsakiyar kowane daga cikin diagonals. Abu na biyu, da ciwon tsakanin wani na daura diagonal vertices, yana yiwuwa a gane cewa duk da nodes da guda batu na rarrabawa. Har ila yau, ya kamata a lura shi ne dukiya da cewa akasin fuskoki ne ko da yaushe kuma dole a layi daya da juna.

A yanayi, wadannan jinsunan suke da daraja parallelepipeds:

• rectangular - shi kunshi fuskokin wani rectangular siffar.

• kai tsaye - yana da kawai da gefen fuskoki da rectangular.

• QFontDatabase parallelepiped ne wani ɓangare na gefen fuskoki, wanda ake tsĩrar da ba-perpendicular filaye.

• Cube - kunshi wani square-dimbin yawa fuskõkinsu.

Bari mu yi kokarin nemo yankin na akwatin a kan misali na rectangular irin siffar. Kamar yadda muka riga sani, duk fuskokin rectangular. Kuma saboda yawan wadannan abubuwa an rage wa shida, sa'an nan zuwa ga gano fannin kowane fuska, kana bukatar ka takaice don samun sakamakon a wani guda lambar. Kuma a sami yankin kowane daga cikinsu ba wuya. Don yin wannan, ninka bangarorin biyu na murabba'i mai dari.

Amfani da wani ilmin lissafi dabara domin sanin fannin wani cuboid. Ya kunshi mafi muhimmanci haruffa a samansu fuska yankin, da kuma shi ne kamar haka: S = 2 (ab + bc + ac), inda S - yanki na adadi, a, b - gefe na da tushe, c - kaikaice gefen.

Mun bayar da wani m lissafi. Ya ɗauka, a = 20 cm, b = 16 cm, c = 10 cm yanzu dole ninka da lambobin daidai da dabara :. 20 * 16 + 16 * 10 + 20 * 10 da samu da yawan 680 cm2. Amma zai kasance ne kawai rabin na adadi, kamar yadda muka rigaya muka koya, kuma sun takaita uku square fuskoki. Tun da kowane fuska yana ta "biyu", anya sakamakon darajar, da kuma samun akwatin yanki daidai 1360 cm 2.

Don lissafi da kaikaice surface area, yi amfani da dabara S = 2c (a + b). A yankin na akwatin tushe za a iya samu ta hanyar halitta da tsawon tarnaƙi daga cikin tushe a juna.

A rayuwar yau da kullum, parallelepipeds za a iya samu akai-akai. Game da su zama mana tuni game da siffar tubalin, katako aljihun tebur na tebur, talakawa matchbox. Misalai na kowanne za a iya samu a yalwace kewaye da mu. Makaranta shirye-shirye a lissafi don nazarin 'yan darussan da aka ba wa akwatin. A farko daga cikin wadannan model nuna wani cuboid. Sai suka nuna da dalibai yadda za a shiga da shi a ball ko dala, wasu alkaluma, to sami yankin na akwatin. A takaice, wannan shi ne mafi sauki uku-girma adadi.