點求球體的半徑!?

設半徑=r 和表面面積=A
36兀=4/3兀r^3
27=r^3
r=3
A=4兀r^2
A=4兀(3)^2
A=36兀
所以
半徑=3和表面面積=36 兀

volume of sphere, 球體的體積 = (4/3)(pi)(r^3) where r is the radius
surface area of sphere, 球體的表面面積 = 4(pi)(r^2)

(4/3)(pi)(r^3) = 36(pi)
r^3 = 27
r = 3

surface area of sphere = 4(pi)(3^2) = 36(pi)

圖片參考：http://i39.tinypic.com/oi7kso.png


http://i39.tinypic.com/oi7kso.png