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正方体有8个顶点,6个面,12条棱,有4条体对角线,有12条侧面对角线,有1个对称中心,有3对互相平行的侧面或者底面,有3组成互相平行的棱,每1组有4条棱,其中有线在平面内,线面平行、垂直,面与面平行、垂直.可以说,立体几何整个体系可以在正方体里面得到体现,因而有“百宝箱”的美称.有许多高考立体几何题,可以构造正方体得到一些巧妙的解法,下面略举几例.
The cube has 8 vertices, 6 faces, 12 edges, 4 body diagonals, 12 side diagonals, 1 symmetry center, 3 pairs of mutually parallel sides or bottom faces, and 3 components each other Parallel edges, each group has 4 edges, in which the wire is in the plane, the line surface is parallel and vertical, and the surface is parallel and vertical to the surface. It can be said that the whole system of the three-dimensional geometry can be embodied in the cube, so there is a “treasure chest” The reputation of the college entrance examination. There are many college entrance examination three-dimensional geometric questions, you can construct a cube to get some clever solutions, the following a few examples.