如图,圆锥的顶点是S,底面中心为O.OC是与底面直径AB垂直的一条半径,D是母线SC的中点.
(1)求证:BC与SA不可能垂直;
(2)设圆锥的高为4,异面直线AD与BC所成角的余弦值为
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101230754966415005/SYS201311012307549664150015_ST/0.png)
,求圆锥的体积.
考点分析:
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△OBC•
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