Video: Puas yog cov kaum sab xis hauv ib daim duab peb sab isosceles ib txwm ntsuas 45?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Hauv ib isosceles txoj cai daim duab peb sab , qhov sib npaug sab ua tus sab xis . Nco ntsoov tias txij li thaum txoj cai daim duab peb sab yog isosceles , tiam lub kaum sab xis ntawm puag sib npaug. (Theorem 3.) Yog li ntawd txhua tus ntawm cov mob lub kaum sab xis yog 45 °.
Tsis tas li ntawd, dab tsi yog qhov ntsuas ntawm cov kaum hauv ib qho isosceles txoj cai daim duab peb sab?
Teb thiab piav qhia: Lub ntsuas ntawm ib lub hauv paus lub kaum sab xis ntawm ib isosceles txoj cai daim duab peb sab yog 45 degrees. Hauv ib qho twg daim duab peb sab , cov ntsuas ntawm tag nrho peb lub kaum sab xis sib npaug 180 degrees.
Qhov thib ob, tus qauv ntawm isosceles yog dab tsi? Tag nrho cov qauv mus nrhiav Isosceles Daim duab peb sab Cheeb Tsam
| Cov qauv los nrhiav thaj tsam ntawm Isosceles Daim duab peb sab | |
|---|---|
| Siv ntev ntawm 2 sab thiab lub kaum sab xis ntawm lawv | A = ½ × b × c × sin(α) |
| Siv 2 lub kaum ntse ntse thiab ntev ntawm lawv | A = [c2x sin(β) × sin(α)/ 2 × sin(2π−α−β)] |
| Cheeb Tsam formula rau isosceles txoj cai daim duab peb sab | Luas = ½ x a2 |
Kuj Paub, puas yog daim duab peb sab kaum ib txwm isosceles?
Tsis yog, ib isosceles daim duab peb sab tsis yog Ib txwm ib txoj cai daim duab peb sab . Ib Isosceles Daim duab peb sab tuaj yeem yog a txoj cai daim duab peb sab , nws yog 45-45-90 degree daim duab peb sab.
Dab tsi yog thaj tsam ntawm daim duab peb sab isosceles?
Yuav nrhiav tau cheeb tsam ntawm ib isosceles daim duab peb sab siv qhov ntev ntawm ob sab, sau qhov ntev ntawm txhua sab, lub hauv paus, thiab qhov siab yog tias nws muab. Tom qab ntawd, siv qhov sib npaug Thaj chaw = ½ lub sij hawm lub hauv paus qhov siab kom pom cov cheeb tsam.
Pom zoo:
Dab tsi yog lub kaum sab xis ntsuas hauv daim duab peb sab ABC?
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