解析“动三角形”问题

• 作 者: 金爱珠
• 机 构: 浙江绍兴
• 出 处: 初中生世界
• 发表日期: 2004年33期
• 关键词: 轴对称图形 数学之美 顶点坐标 中考试题 探索活动 对应点 旋转中心 数量关系 直角坐标系 数形结合

三角形的旋转、折叠、移动、对称问题成了近年来各地中考试题中的一道亮丽风景.这类题形式多样,需要采用数形结合的方法,并通过观察、操作、猜想、推理、计算等一系列数学探索活动才能获得解决.一、转1.平面上的旋转例1(济南市)如图1,在直角坐标系中,△ABC各顶点坐标分别为A(0,

The problems of rotation, folding, movement, and symmetry of triangles have become a beautiful landscape in the examination questions in various localities in recent years. These types of questions are diverse in form and require the use of a combination of numbers and shapes, as well as observation, manipulation, guessing, reasoning, and calculation. A series of mathematical exploration activities can be resolved. First, turn 1. Rotation on the plane Example 1 (Jinan) In Figure 1, in the Cartesian coordinate system, the coordinates of each vertex of ABC are A (0, respectively).