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单位向量是向量的一个重要概念,本文例谈对它的深层次理解巧解题.1应用单位向量定义从数上来深层次理解巧解题向量a为单位向量|a|=1;因为a|a|=||aa||=1,所以|aa|是非零向量a方向上的单位向量.例1(2002年全国高中数学联赛山东赛区预赛题)设O为△ABC内任一点,SA,SB,SC分别表示△B
The unit vector is an important concept of the vector. The example of this article discusses its deep understanding of the problem and solves the problem. 1 The application unit vector defines the number from the depth to understand the problem. The solution vector a is the unit vector |a|=1; because a| a|=||aa||=1, so |aa| is a unit vector in the non-zero vector a direction. Example 1 (2002 National High School Mathematics League Shandong Division Preliminary Challenge) Let O be any point in △ABC, SA, SB, SC respectively represent △B