Question

pirqmida triunghiulara regulata vabc are inaltimea vo=6cm si latura bazei Ab==18 cm.Calculati: a)d(O(vab)) b.d(C(Vab))​

Answer 1

Răspuns:

Explicație pas cu pas:

VM²=VO²+OM²  OM=18√3/6=2√3   VO=6 cm

VM=√12+36=√48=4√3 cm

a)d(O(vab))=d(O(vcb)) ducem OP⊥VM  Calculam aria Δ VOM

VO×OM=VM×OP      6×2√3=4√3×x      OP=12 cm

b) d(C(Vab))​  CR⊥AB si CT⊥VR

CR=18√3/2=9√3 cm

calculam aria ΔVCR in 2 moduri

CT×VR=CR×AB    VR=apotema=VM=4√3 cm

CT×4√3=9√3×18   CT=9×18/4cm