Question

O piramida triunghiulara regulata cu latura=18, volumul de 18, si inaltimea 6 radical 3. Aflati: S lat, S tot, V. Dau coroana va rog e urgent!!!!!!​

Answer 1

Răspuns:

Explicație pas cu pas:

V=Ab·h/3     =81√3·6√3/3=486 cm³

Ab=l²√3/4    ⇒Ab=18²√3/4=81√3 cm²

apotema Δ=l√3/2·1/3=l√3/6=18√3/6=3√3 cm

Apotema piramidei²=h²+ap²=6²+9·3=36·3+27=108+27=135=3³·5

Ap=9√15cm

Al=P·Ap/2=3·6·9√15/2=81√15 cm²

At=Ab+Al=81√3+81√15=81√3(1+√5) cm²