txheem
Hauv tsab xov xwm no, peb yuav txiav txim siab lub ntsiab lus thiab cov khoom ntawm daim duab peb sab sib npaug (tsis tu ncua) . Peb kuj tseem yuav tshuaj xyuas ib qho piv txwv ntawm kev daws teeb meem los sib sau ua ke cov khoom siv theoretical.
Kev txhais ntawm daim duab peb sab sib npaug
Sib Luag (los yog muaj tseeb) yog hu ua daim duab peb sab uas txhua sab muaj qhov ntev. Cov. AB = BC = AC.
Nco ntsoov: Ib lub polygon tsis tu ncua yog ib qho convex polygon nrog sib npaug sab thiab cov ces kaum ntawm lawv.
Cov khoom ntawm daim duab peb sab equilateral
Khoom Muaj Khoom 1
Hauv daim duab peb sab sib npaug, txhua lub kaum sab xis yog 60 °. Cov. α = γ = 60°.
Khoom Muaj Khoom 2
Nyob rau hauv ib daim duab peb sab sib npaug, qhov siab kos mus rau ob sab yog ob qho tib si lub bisector ntawm lub kaum sab xis uas nws tau kos, nrog rau qhov nruab nrab thiab lub perpendicular bisector.
CD - nruab nrab, qhov siab thiab perpendicular bisector rau sab AB, nrog rau lub kaum sab xis bisector ACB.
- CD txiav tawm AB => ∠ADC = ∠BDC = 90°
- AD = IB
- ∠ACD = ∠DCB = 30°
Khoom Muaj Khoom 3
Hauv ib daim duab peb sab sib npaug, cov bisectors, nruab nrab, qhov siab thiab perpendicular bisectors kos rau txhua sab sib tshuam ntawm ib qho.
Khoom Muaj Khoom 4
Cov chaw nruab nrab ntawm cov ntawv sau thiab cov voj voog ncig ib ncig ntawm daim duab peb sab sib npaug sib npaug thiab yog nyob ntawm kev sib tshuam ntawm nruab nrab, qhov siab, bisectors thiab perpendicular bisectors.
Khoom Muaj Khoom 5
Lub vojvoog ntawm lub voj voog ncig ib ncig ntawm daim duab peb sab sib npaug yog 2 npaug ntawm lub vojvoog ntawm lub voj voog inscribed.
- R yog lub vojvoog ntawm lub voj voog ncig;
- r yog lub vojvoog ntawm lub voj voog inscribed;
- R = 2 r.
Khoom Muaj Khoom 6
Hauv daim duab peb sab sib npaug, paub qhov ntev ntawm sab (peb yuav conditionally coj nws li “rau”), peb tuaj yeem xam:
1. Qhov siab / nruab nrab / bisector:
2. Radius ntawm lub voj voog inscribed:
3. Radius ntawm lub voj voog ncig:
4. Ib puag ncig:
5. cheeb tsam:
Piv txwv ntawm qhov teeb meem
Ib daim duab peb sab sib npaug yog muab, sab uas yog 7 cm. Nrhiav lub vojvoog ntawm lub voj voog ncig thiab sau lub voj voog, nrog rau qhov siab ntawm daim duab.
tshuaj
Peb siv cov qauv uas tau muab los saum toj no kom pom cov khoom tsis paub:
