Contents
A cikin wannan ɗaba'ar, za mu yi la'akari da ainihin kaddarorin tsayi a cikin madaidaicin alwatika (na yau da kullun). Za mu kuma yi nazarin misali na warware matsala kan wannan batu.
lura: ana kiran triangle daidaitacceidan dukkan bangarorinta daidai suke.
Kaddarorin tsayi a cikin madaidaicin alwatika
Kadarori 1
Duk wani tsayi a cikin madaidaicin triangle duka biyun bisector ne, tsaka-tsaki, da madaidaicin bisector.
- BD – tsawo saukar zuwa gefe AC;
- BD shine tsaka-tsakin da ke raba gefe AC cikin rabi, watau AD = DC;
- BD - kusurwa bisector ABC, watau ∠ABD = ∠CBD;
- BD shine matsakaicin perpendicular zuwa AC.
Kadarori 2
Dukkanin tsaunuka uku a cikin madaidaicin alwatika suna da tsayi iri ɗaya.
AE = BD = CF
Kadarori 3
Matsakaicin tsayi a cikin madaidaicin alwatika a madaidaicin orthocenter (maganin tsaka-tsaki) an raba su a cikin rabo na 2: 1, ana ƙirgawa daga ƙarshen abin da aka zana su.
- AO = 2 OE
- BO = 2 OD
- CO = 2OF
Kadarori 4
Ƙaƙwalwar madaidaicin triangle ita ce tsakiyar da'irar da aka rubuta da da'ira.
- R shine radius na da'irar da aka kewaye;
- r shine radius na da'irar da aka rubuta;
- R = 2r (ya biyo daga Kayayyaki 3).
Kadarori 5
Tsayi a cikin madaidaicin alwatika yana raba shi zuwa yanki guda biyu daidai-daidai (daidaicin yanki) triangles masu kusurwa-dama.
S1 = S ba2
Tsayi uku a cikin madaidaicin alwatika sun raba shi zuwa triangles dama 6 na daidai yanki.
Kadarori 6
Sanin tsawon gefen triangle daidai, ana iya ƙididdige tsayinsa ta hanyar dabara:
a shine gefen triangle.
Misalin matsala
Radius na da'irar da aka kewaye a kusa da madaidaicin alwatika shine 7 cm. Nemo gefen wannan triangle.
Magani
Kamar yadda muka sani daga dukiya 3 и 4, radius na da'irar da aka yi dawafi shine 2/3 na tsayin madaidaicin triangle (h). Sakamakon haka, h = 7 ∶ 2 ⋅ 3 = 10,5 cm.
Yanzu ya rage don ƙididdige tsawon gefen triangle (kalmar ta samo asali ne daga dabarar a cikin Kadarori 6):
