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题目已知三棱锥的三条侧棱两两垂直,底面积为1,求此三棱锥体积的最大值.分析这是2012年全国高中数学联赛新疆预选赛的压轴题,本题如果对已知条件“三棱锥的三条侧棱两两垂直”分析到位的话,就可以利用坐标法进行解答,就会比命题组提供的解答方法(见文[1])简单易行.解在三棱锥O-ABC中,因为OA、OB、OC两两垂直,以O为坐标原点,OA、OB、OC所在直线分别为x轴、y轴、z轴建立空间直角
Title Three pyramids of the three side edges perpendicular to each other, the bottom area of 1, and find the maximum value of the volume of the pyramid. Analysis This is the 2012 national high school marathon Xinjiang qualifier finale title, the question if the known conditions “Triangular pyramid of the two sides of two vertical two ” analysis in place, then you can use the coordinate method to answer, than the proposition group provides the answer method (see [1]) is simple and easy solution to the triangular pyramid O- ABC, because OA, OB, OC two or two perpendicular to O as the origin of coordinates, OA, OB, OC where the lines were x-axis, y-axis, z-axis to establish space at right angles