Completati tabelul urmator (au fost folosite notatiile obisnuite pentru cilindru ) a) r = 10 : g =12 : At = ? : Al =? : V= ? b) Al = 96 pi : At = 168 pi : V =? : g=? : r =? c) r = 3 : At = 78 pi : V =? At = ? : Al=? : g = ?

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Răspunsuri

2014-05-10T11:51:05+03:00
A) Al= 2πrg = 2 x 10 x 12 xπ = 240π
At=2πr(r+g)= 2 x π x 10 (10 + 12) = 20π x 22 = 440π
V=πr²g= π x 10² x 12 = 1200π
b) 2Ab= At- Al
Ab= (168-96): 2
Ab= 36π
πr²= 36π
r=√36
r= 6cm

Al= 2πrg
96 π = 2π x 6 x g
96 = 12 g
g= 96: 12
 g= 8 cm

V=πr²g=π 6² x 8 = 288π


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