Ukuphakama mbhoshongo. Kanjani ukuyithola?

Pyramid - a polyhedron, kumila okuyinto ipholigoni. Zonke ubhekene bazabela ifomu onxantathu ezihlangabezana kwelinye vertex. Imibhoshongo aboncathathu, quadrilateral nokunye. Ukuze ukwazi ukubona ukuthi yini mbhoshongo phambi kwakho, kwanele ukubala inani engeli phansi yayo. Sencazelo "ukuphakama mbhoshongo" kuvamile geometry e izinhloso lwezifundo. Lesi sihloko izozama cabanga ngezindlela ezahlukene abayitholayo.

izingxenye mbhoshongo

mbhoshongo ngasinye siqukethe izinto ezilandelayo:

• uhlangothi ubuso ezithinta engela emithathu bukhomba ngesikhathi vertex;
• apothem limelela ukuphakama ukuthi yehla kusuka phezulu yayo;
• phezulu mbhoshongo - iphuzu exhumanisa emaphethelweni lateral, kodwa lokhu akuncikile indiza ye isizinda;
• isizinda - a ipholigoni, okuyinto ingeyona ichopho;
• ukuphakama mbhoshongo liyingxenye ehlangana phezulu mbhoshongo futhi isisekelo salo yakha engela kwesokudla.

Indlela yokuthola ukuphakama mbhoshongo, uma wazi umthamo yayo

Ngemva ifomula mbhoshongo ivolumu V = (S * h) / 3 (e-V ifomula - ivolumu, S - endaweni base, h - ukuphakama mbhoshongo), sithola ukuthi h = (3 * V) / S. Ukuhlanganisa impahla, ake ukuxazulula inkinga ngokushesha. I esingunxantathu mbhoshongo square elisekela 50 cm ^2, ngenkathi ivolumu salo 125 cm ^3. ukuphakama engaziwa of iphiramidi elingunxantathu, futhi lapho sidinga ukuthola. Kulula: faka idatha ku-formula yethu. We ukuthola h = (3 * 125) / 50 = 7,5 cm.

Indlela yokuthola ukuphakama mbhoshongo, uma sazi ubude idayagonali futhi emaphethelweni alo

Njengoba sikhumbula, ukuphakama mbhoshongo kwenza nge isisekelo sayo engela kwesokudla. Lokhu kusho ukuthi ukuphakama ubambo nohhafu ngokuphambeneyo ndawonye bakha unxantathu wesokudla-angled. Abaningi Yiqiniso, ukukhumbula theorem kaPythagoras. Ukwazi izilinganiso ezimbili, ukubaluleka yesithathu ibe lula ukuthola. Khumbula eyaziwa theorem a² = b² + c², futhi lapho - the hypotenuse, futhi kulesi simo onqenqemeni mbhoshongo; b - emlenzeni wokuqala noma isigamu idayagonali futhi - ngokulandelana, umlenze wesibili noma ukuphakama mbhoshongo. Kule c² ifomula = a² - b².

Manje inkinga: ku idayagonali kwesokudla mbhoshongo 20 cm, kuyilapho ubude onqenqemeni - 30 cm ukuphakama kumele batholwe .. Xazulula: c² = 30² - 20² = 900-400 = 500. Ngakho, = √ 500 = mayelana 22.4.

Indlela yokuthola ukuphakama mbhoshongo ufushanisiwe

Kuyinto ipholigoni, okuyinto esinomfuziselo isigaba isisekelo sayo. Ukuphakama iphiramidi ufushanisiwe - ingxenye exhumanisa ezimbili ekusungulweni yayo. Ukuphakama ingatholakala mbhoshongo njalo, empeleni iyokwaziwa ngisho uma ubude diagonals izisekelo ezimbili, futhi onqenqemeni mbhoshongo. Ake idayagonali base enkulu elilingana D1, kuyilapho ezincane isisekelo idayagonali - D2, futhi onqenqemeni has a ubude - l. Ukuze uthole ukuphakama kungaba esekuphakameni ezimbili okuphambene engenhla umdwebo amaphuzu aphansi phansi yayo. Sibona ukuthi sinezinto onxantathu ezimbili kwesokudla, luhlala ukuthola ubude imilenze. Ngenxa yalesi idayagonali enkulu a Khupha ezincane futhi hlukanisa imali yazo ngo 2. Njengoba omunye umlenze sithola: a = (D1-D2) / 2. Ngemva kwalokho, ngokuvumelana theorem kaPythagoras, singakwazi kuphela ukuthola Umlenze wesibili, okuyinto ukuphakama mbhoshongo.

Manje sibheke zonke icala practice. Umsebenzi phambi kwethu. Isivivane ufushanisiwe has isikwele phansi, base enkulu ubude idayagonali 10 cm, kuyilapho ezincane - 6 cm, futhi fin ilingana 4 cm ukuphakama liyadingeka ukuthola .. Ukuze uthole ekuqaleni omunye umlenze a = (10-6) / 2 = 2 cm Umlenze owodwa elilingana 2 cm, kanti hypotenuse - 4 cm kuvela ukuthi Umlenze wesibili noma ukuphakama kuyoba ulingana 16-4 = 12, isb h = .. √12 = mayelana 3.5 cm.