Question

Va rog frumos ajutati-ma !
Multumesc !
Exercitiile : 3,5,7

Answer 1

3.a)a(b)=√a(p)²-h²=√100-64=√36=6cm
b)a(b)=l√3/6⇒l=a(b)·6/√3=6·6/√3=36/√3=12√3cm
c)A(lat)=3·a(p)·l/2=3·10·12√3/2=180√3cm²
d)V=1/3·h·A(bazei)=1/3·8·(12√3)²/4=2·432/3=288cm³
[A(bazei)=l²√3/4]
e)m²=a(p)²+(l/2)²
m²=100+108
m=√208=4√13cm
5.VM=2cm
AM=3√3cm
AB=6cm
VA=√13cm
7.a)h=l√6/3=6√2·√6/3=2√12=4√3cm
b)a(b)=l√3/6=6√2·√3/6=√6cm
c)A(lat)=3l²√3/4=3(6√2)²/4=3·72·√3/4=54√3cm²
d)V=1/3·A(bazei)·h=l³·√2/12=(6√2)³·√2/12=216·2√2·√2/12=72cm³
e)m²=a(p)²+(l/2)²
m²=(√7)²+(3√2)²=7+18=25
m=√25=5cm
a(p)=apotema piramidei;a(b)=apotema bazei