Răspunsuri

2014-05-12T20:47:21+03:00
R,h  dp cu 3,4  
r/3=h/4=k
r=3k
h=4k
V=πr²*h/3= (3k)²*4k π/3= 9k²*4k π/3= 36k³ π/3= 12 k² π
V=768 π

12k² π=768 π
12k²=768
k²=64
k=8

r=24
h=32

At=Al+Ab
Ab=πr²= 24²π= 576π
Al=π r*g= 24*32 π=768 π

At=576+768=1344π

ΔVOB, mas<O=90
VB²=VO²+OB²=24²+32²=576+1024= 1600  ⇒VB=40
P=2*40+2*24=80+48=128