the figure shows a solid hemisphere of radius 18 cm. It is cut into three portions, S, T and W, along two planes parallel to its base.Let Vs cm^3, Vt cm^3 and Vw cm^3 be the volume of S, T and W respectively, 2h cm and h cm be the heights of S and T respectively.
It is given that Vs is partly varies directly as h^2 and partly varies directly as h^3. When h=2, Vs=800pi/3 and when h=3, Vs=576pi
(Q): express Vt in terms of h and pi.
f.4 maths(only1Q) urgent!!
2011-09-30 2:46 am
回答 (2)
2011-09-30 3:53 am
✔ 最佳答案
(a) Let V(S) = Ah^2 + Bh^34A + 8B = 800π/3
9A + 27B = 576π
B = -8π/3, A = 72π
V(S) = 72πh^2 - (8π/3)h^3
V(S + T) = (9/4)(72π)h^2 - (27/8)(8π/3)h^3
= 162πh^2 - (27π/3)h^3
V(T) = 90πh^2 + (19π/3)h^3
2011-09-29 19:53:51 補充：
V(T) = 90πh^2 - (19π/3)h^3
2011-10-02 1:56 am
請問V(S + T) = (9/4)(72π)h^2 - (27/8)(8π/3)h^3 中(9/4)和(27/8)是怎樣找出來的 thz!~
收錄日期: 2021-04-13 18:16:18
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