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Video: Yuav ua li cas koj pom tus nqi ntawm cosine ntawm daim duab peb sab?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Nyob rau hauv txhua txoj cai daim duab peb sab , cov cosine ntawm ib angle yog qhov ntev ntawm sab uas nyob ib sab (A) faib los ntawm qhov ntev ntawm lub hypotenuse (H). Nyob rau hauv ib tug formula, nws yog sau yooj yim li ' cos '. Feem ntau nco ntsoov ua "CAH" - lub ntsiab lus Cosine nyob ib sab dhau Hypotenuse.
Ua li no, koj yuav nrhiav tau tus cosine ntawm daim duab peb sab li cas?
Nyob rau hauv txhua txoj cai angled daim duab peb sab, rau txhua lub kaum sab xis:
- Lub sine ntawm lub kaum sab xis = qhov ntev ntawm qhov opposite sab. qhov ntev ntawm lub hypotenuse.
- Lub cosine ntawm lub kaum sab xis = qhov ntev ntawm sab uas nyob ib sab. qhov ntev ntawm lub hypotenuse.
- Lub tangent ntawm lub kaum sab xis = qhov ntev ntawm qhov opposite sab. qhov ntev ntawm sab uas nyob ib sab.
Ib sab saum toj no, COS sib npaug li cas? Ib txwm, ib txwm, lub sine ntawm lub kaum sab xis yog sib npaug sab nraud faib los ntawm hypotenuse (opp / hyp hauv daim duab). Cov cosine yog sib npaug sab uas nyob ib sab faib los ntawm hypotenuse (adj/hyp).
Kuj nug, dab tsi yog qhov kev txhaum cos thiab tan ntawm daim duab peb sab?
Lub sine ntawm ib lub kaum sab xis ntawm ib txoj cai daim duab peb sab (feem ntau abbreviated " kev txhaum ") yog qhov piv ntawm qhov ntev ntawm sab ntawm lub daim duab peb sab opposite lub kaum sab xis rau qhov ntev ntawm lub daim duab peb sab hypotenuse. TSI → kev txhaum = "opposite" / "hypotenuse" CAH → cos = "adjacent" / "hypotenuse" TOA → tan = "opposite" / "adjacent"
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.
Pom zoo:
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