Video: Puas yog txoj cai cosine ua haujlwm rau txhua daim duab peb sab?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Los ntawm qhov ntawd, koj ua tau siv lub Txoj cai ntawm Cosines mus nrhiav qhov thib peb. Nws ua haujlwm ntawm tej daim duab peb sab , tsis yog lawm daim duab peb sab . qhov twg a thiab b yog ob sab muab, C yog lawv lub kaum sab xis, thiab c yog qhov thib peb tsis paub.
Ua li no, koj puas tuaj yeem siv txoj cai cosine rau txoj cai daim duab peb sab?
Lub pythagorean theorem yog li tsuas yog siv rau txoj cai daim duab peb sab hos cov txoj cai ntawm cosines tau siv rau ib qho twg daim duab peb sab.
Ib sab saum toj no, txoj cai cosine rau daim duab peb sab yog dab tsi? Txoj Cai Cosine (The Law of Cosine ) Cov Txoj Cai Cosine hais tias qhov square ntawm qhov ntev ntawm ib sab ntawm a daim duab peb sab sib npaug qhov sib npaug ntawm cov squares ntawm qhov ntev ntawm lwm sab rho tawm ob zaug lawv cov khoom muab faib los ntawm cosine ntawm lawv lub kaum sab xis.
txoj cai cosine siv tau rau txhua daim duab peb sab?
Txoj Cai Cosine . Cov Txoj Cai Cosine tuaj yeem siv hauv tej daim duab peb sab qhov twg koj tab tom sim txheeb tag nrho peb sab rau ib lub kaum sab xis. Yog tias koj xav pom qhov ntev ntawm ib sab, koj yuav tsum paub txog ob sab thiab lub kaum sab nraud.
Vim li cas daim duab peb sab txoj cai ntawm cosines siv?
Cov txoj cai ntawm cosines yog pab tau rau xam qhov thib peb ntawm a daim duab peb sab Thaum ob sab thiab lawv lub kaum sab xis raug paub, thiab hauv kev suav cov kaum ntawm a daim duab peb sab yog paub tag nrho peb sab.
Pom zoo:
Dab tsi yog equidistant los ntawm peb sab ntawm daim duab peb sab?
Lub ntsiab lus uas sib npaug rau txhua sab ntawm daim duab peb sab yog hu ua incenter: Ib qho nruab nrab yog ib qho kab uas muaj ib qho ntawm nws qhov kawg ntawm lub vertex ntawm daim duab peb sab thiab lwm qhov kawg ntawm qhov nruab nrab ntawm sab opposite lub vertex. Peb qhov nruab nrab ntawm ib daim duab peb sab sib ntsib hauv centroid
Koj tuaj yeem ua pov thawj li cas 2 daim duab peb sab zoo sib xws siv lub kaum sab xis sab SAS zoo sib xws postulate?
SAS Similarity Theorem hais tias yog ob sab hauv ib daim duab peb sab yog proportional rau ob sab hauv lwm daim duab peb sab thiab lub kaum sab xis nyob rau hauv ob qho tib si congruent, ces ob daim duab peb sab zoo ib yam. Ib qho kev hloov pauv zoo sib xws yog ib lossis ntau qhov kev hloov pauv tsis tu ncua ua raws li kev dilation
Vim li cas nws thiaj li hais tias lub Orthocenter ntawm daim duab peb sab obtuse yuav tsum nyob rau sab nraud ntawm daim duab peb sab?
Nws hloov tawm tias tag nrho peb qhov siab ib txwm sib tshuam ntawm tib lub ntsiab lus - lub npe hu ua orthocenter ntawm daim duab peb sab. Lub orthocenter tsis yog ib txwm nyob hauv daim duab peb sab. Yog tias daim duab peb sab yog obtuse, nws yuav nyob sab nraud. Txhawm rau ua kom qhov no tshwm sim cov kab qhov siab yuav tsum tau txuas ntxiv kom lawv hla
Dab tsi yog qhov txawv ntawm lub xeev daim duab kos duab thiab daim duab ua haujlwm?
Lub xeev daim duab qauv yog siv los qhia qhov sib lawv liag ntawm lub xeev uas ib yam khoom mus dhau, qhov ua rau kev hloov ntawm ib lub xeev mus rau lwm qhov thiab qhov kev txiav txim uas tshwm sim los ntawm lub xeev hloov. Daim duab ua haujlwm yog ntws ntawm kev ua haujlwm yam tsis muaj qhov tshwm sim (kev tshwm sim) mechanism, lub xeev tshuab yog suav nrog lub xeev triggered
Dab tsi yog kev sib raug zoo ntawm sab nrauv thiab sab hauv lub kaum sab xis ntawm daim duab peb sab?
Cov kaum sab hauv yog hu ua Sab hauv cov ces kaum. Cov lej ntawm cov kaum sab hauv ntawm daim duab peb sab yog ib txwm 180 degrees. Lub kaum sab nrauv yog lub kaum sab xis ntawm ib sab ntawm ib qho duab, thiab ib txoj kab txuas ntxiv los ntawm sab tom ntej. Qhov sib npaug ntawm lub kaum sab nrauv thiab nws lub kaum sab hauv uas nyob ib sab kuj yog 180 degrees