Kubning sirti va qirralarini topishga doir masalalarni yechish To`g`ri

B1
C1
A1
D1
c
b
A
B
a
C
D
a
a
a
6 ta
Masala
Kubning qirrasi uzunligi 5 smga teng. Kub
sirti yuzini toping.
Berilgan: a=5 sm
Topish kerak S=?
Yechish:
Kub sirti yuzi formalasidan foydalanamiz:
a
a
a
a
a
a
a
a
a
a
a
a
Kubning qirrasi uzunligi 2 smga teng.
Barcha qirralari yig’indisini toping.
Berilgan: a=2 sm
Topish kerak l=?
Yechish:
Barcha qirralari yig’indisini l=12a formuladan
topamiz:
Topshiriq
Shakl
Nomi
Parallelepiped
Kub
Kub
Parallelepiped
Masalani yeching.
Berilishi:
Kub berilagan.
Qirrasi uzunligi a=6 sm.
a
Topish kerak:
1) kub sirti yuzi S=?
2) barcha qirralari
yig’indisi l=?
Masalaning yechimi
Sirtini yuzini topish:
Barcha qirralari yig’indisini topish:
l=12a=12*6=72 (sm)
Parallelepiped masalasini yeching.
Berilishi:
To’g’ri burchakli
parallelepiped berilagan.
Qirralari uzunliklari mos
ravishda bo’yi b=2 sm, eni
c=3 sm, balandligi a=6 sm
a
b
c
Topish kerak:
1) Parallelepiped sirti
yuzi S=?
2) barcha qirralari
yig’indisi l=?
Formulasi
Parallelepiped sirtini yuzi:
S=2(ab+ac+bc)
Parallelepiped barcha qirralari
yig’indisi:
l=4(a+b+c)
Parallelepiped masalasini yechimi:
Sirtini yuzini topish:
S=2(ab+ac+bc)=2(6*2+6*3+2*3)=
2(12+18+6)==2*36=72
Barcha qirralari yig’indisini topish:
l=4(a+b+c)=4(6+2+3)=4*11=44 (sm)
Masalani yeching.
a
a
a
a
a
a
a
a
a
Berilishi:
Kub berilgan.
Uning barcha qirralari
a uzunliklari yig’indisi
l=84 sm
a
a
Topish kerak:
Kubning qirrasi uzunligi
a=?
Sirtini yuzi S=?
Masalani yechimi:
Avval kubning qirralari yig’indisidan uning bitta qirrasi uzunligini
topib olamiz
a=l:12=84:12=7 (sm)
Endi kub sirtini yuzini topamiz: