Video: Puas yog daim duab peb sab isosceles muaj ob lub kaum sab xis?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Thaum a daim duab peb sab muaj ob sab congruent hu ua ib isosceles daim duab peb sab . Cov lub kaum sab xis opposite rau ob sab ntawm tib qhov ntev yog concruent . A daim duab peb sab tsis muaj kev sib haum xeeb los yog lub kaum sab xis hu ua scalene daim duab peb sab.
Tsuas yog li ntawd, muaj pes tsawg lub kaum sab xis ntawm daim duab peb sab isosceles?
ob lub kaum sab xis
Tom qab ntawd, lo lus nug yog, dab tsi yog qhov 2 congruent sab ntawm daim duab peb sab isosceles hu ua? Ib isosceles daim duab peb sab yog a daim duab peb sab uas muaj tsawg kawg yog ob kev sib haum xeeb . Cov kev sib haum xeeb ntawm isosceles daim duab peb sab yog hu ua ob txhais ceg. Lwm tus sab yog hu ua lub hauv paus. Lub kaum sab xis ntawm lub hauv paus thiab ob txhais ceg yog hu ua puag cov ces kaum. Lub kaum sab xis ua los ntawm ob txhais ceg yog hu ua lub kaum sab xis.
Ntxiv mus, puas yog daim duab peb sab isosceles muaj cov kaum sab xis sib dhos?
Cov puag cov ces kaum ntawm ib isosceles daim duab peb sab tus lub kaum sab xis tsim los ntawm cov puag thiab ib ceg ntawm lub daim duab peb sab . Cov puag cov ces kaum theorem converse hais tias yog ob lub kaum sab xis hauv a daim duab peb sab yog congruent , ces ob sab opposite cov cov ces kaum yog kuj kev sib haum xeeb.
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 |
Pom zoo:
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