2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
ABC yog daim duab peb sab sib npaug, qhov twg D taw qhia rau sab BC hauv txoj hauv kev uas BD=BC/3. Cia E yog taw tes rau sab BC li AE⊥BC.
Yuav ua li cas Trisect ib daim duab peb sab sib npaug?
Tau trisect daim duab peb sab qub, peb yuav tsum faib daim duab peb sab loj (AIC) ua ob daim duab peb sab sib npaug. Qhov no tuaj yeem ua tiav los ntawm kev nrhiav qhov nruab nrab ntawm txhua sab ntawm daim duab peb sab thiab tsim cov ntu los ntawm lawv mus rau qhov rov qab vertex. Ob txoj kev tuaj yeem pom hauv qab no.
Koj ua li cas ua pov thawj tias daim duab peb sab ABC yog daim duab peb sab sib npaug?
Peb paub tias txhua sab ntawm daim duab peb sab sib npaug sib npaug, txhais tau tias hauv daim duab peb sab ABC, peb muaj AB=BC=AC. Peb paub tias cov kaum sab nraud ntawm qhov sib npaug ntawm daim duab peb sab yog sib npaug. Yog li, ntawm no peb muaj sab AB sib npaug rau sab AC, txhais tau tias ∠B=∠C………
Puas yog tag nrho cov kaum hauv ib daim duab peb sab sib npaug?
Sal ua pov thawj tias lub kaum sab xis ntawm daim duab peb sab sib npaug yog tag nrho congruent (thiab yog li ntawd lawv txhua tus ntsuas 60 °), thiab qhov sib txawv, cov duab peb sab nrog txhua lub kaum sab xis yog sib npaug.
Dab tsi yog sab ntawm daim duab peb sab sib npaug?
Hauv geometry, daim duab peb sab sib npaug yog daim duab peb sab uas tag nrho peb sab muaj qhov ntev tib yam. Nyob rau hauv cov Euclidean geometry paub, ib daim duab peb sab equilateral kuj equiangular; uas yog, tag nrho peb lub kaum sab hauv kuj muaj kev sib koom ua ke thiab yog txhua 60 °.
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:
Puas yog daim duab peb sab nrog ob sab sib npaug?
Isosceles Isosceles. Daim duab peb sab isosceles tuaj yeem kos rau ntau txoj hauv kev. Nws tuaj yeem kos kom muaj ob sab sib npaug thiab ob lub kaum sib npaug lossis nrog ob lub kaum ntse ntse thiab ib lub kaum obtuse. Nws yog ib qho yooj yim los ua kom tiav cov ces kaum uas ploj lawm ntawm daim duab peb sab isosceles los ntawm kev nrhiav cov ces kaum uas yuav tsum sib npaug.
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.
