2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Feem ntau, lub cosine ntawm obtuse lub kaum sab xis yog qhov tsis zoo ntawm cosine ntawm nws cov ntxiv. … Yog li, txoj cai ntawm cosines siv tau thaum C yog lub kaum sab xis. Case 2. Tam sim no xav txog cov ntaub ntawv thaum lub kaum sab xis ntawm C yog lawm.
Koj puas pom cov cosine ntawm lub kaum sab xis?
cos θ=−cos (180° − θ), where 90° < θ < 180°. Nyob rau hauv cov lus no hais tias: lub sine ntawm lub obtuse lub kaum sab xis sib npaug ntawm lub sine ntawm nws ntxiv, lub cosine ntawm lub obtuse lub kaum sab xis sib npaug rho tus cosine ntawm nws ntxiv.
Yuav siv txoj cai cosine ntawm ib daim duab peb sab?
Txoj Cai Cosine tuaj yeem siv tau hauv txhua daim duab peb sab uas koj tab tom sim txheeb tag nrho peb sab rau ib lub kaum. Yog tias koj xav pom qhov ntev ntawm ib sab, koj yuav tsum paub ob sab thiab lub kaum sab xis.
Txoj cai rau obtuse daim duab peb sab yog dab tsi?
Nyob rau hauv daim duab peb sab obtuse, yog tias ib lub kaum sab xis ntsuas ntau dua 90 °, ces qhov sib npaug ntawm ob lub kaum sab xis ntxiv yog tsawg dua 90 °. Ntawm no, daim duab peb sab ABC yog daim duab peb sab obtuse, vim ∠A ntsuas ntau tshaj 90 degrees. Txij li thaum, ∠A yog 120 degrees, qhov sib npaug ntawm ∠B thiab ∠C yuav tsawg dua 90° degrees.
Koj puas tuaj yeem siv txoj cai cosine uas tsis yog lub kaum sab xis?
Txoj Cai Cosines yuav tsum siv rau txhua qhov oblique (tsis yog txoj cai) daim duab peb sab.
Pom zoo:
Lub kaum sab xis twg tuaj yeem tsim daim duab peb sab?
Daim duab peb sab kuj tuaj yeem raug cais los ntawm lawv cov kaum. Hauv daim duab peb sab mob daim duab peb sab tag nrho peb lub kaum sab xis yog mob (tsawg dua 90 degrees). Daim duab peb sab txoj cai muaj ib lub kaum sab xis thiab ob lub kaum sab xis.
Lub kaum sab xis yog daim duab peb sab?
Triangle angle sum theorem: Qhov no hais tias cov lej ntawm tag nrho peb lub kaum sab hauv sab hauv Lub kaum sab xis Nyob rau hauv geometry, lub kaum sab hauv ntawm daim duab peb sab yog cov kaum sab xis uas tsim hauv daim duab peb sab. Cov ces kaum sab hauv muaj cov khoom nram qab no:
Vim li cas thiaj siv daim ntaub qhwv daim duab peb sab?
Ib daim duab peb sab yog siv ua ib caj npab lossis ua lub ncoo los tswj ntshav. Nws kuj tseem siv tau los txhawb lossis immobilize qhov raug mob rau pob txha lossis pob qij txha los yog ua padding ua rau mob hnyav. Cov ntaub qhwv lub cev yog siv los khaws cov hnav khaub ncaws ntawm tus ntiv tes lossis ntiv taw.
Thaum twg peb xav txog daim duab peb sab ua equiangular?
Ib daim duab peb sab uas nws tag nrho peb sab thiab sab hauv cov ces kaum sib npaug yog hu ua daim duab peb sab equiangular. Rau ib daim duab peb sab kom sib npaug, qhov ntsuas ntawm tag nrho nws peb lub kaum sab hauv yuav tsum sib npaug li 60 degrees.
Puas yog daim duab peb sab txoj cai ntawm vector ntxiv?
Daim duab peb sab txoj cai ntawm vector ntxiv hais tias thaum ob lub vectors sawv cev ua ob sab ntawm daim duab peb sab nrog qhov kev txiav txim ntawm qhov loj thiab kev taw qhia, ces sab thib peb ntawm daim duab peb sab sawv cev qhov loj thiab kev taw qhia ntawm resultant vector.
