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一、旋转变换及其性质1.旋转变换在平面内,将一个图形绕某一定点,按顺时针(或逆时针)方向旋转一个角度,得到另一个图形,这样的图形变换叫旋转变换,简称旋转.2.旋转变换的性质①变换后的图形与原图形全等;②对应点到旋转中心的距离相等;③对应线段的所在直线的夹角等于旋转角.二、提炼旋转法旋转法就是在图形具有“公共端点的相等线段且其夹角为特殊角”的特征时,可以把图形或图形的一部分绕
First, the rotation transformation and its nature 1. Rotation Transformation In the plane, a graphic around a fixed point, clockwise (or counterclockwise) direction of rotation of an angle, to get another graphic, such a graphics transform called rotation transform, referred to as Rotation .2 the nature of rotation transform ① converted graphics and the original graphics congruent; ② corresponding point to the center of rotation is equal to the distance; ③ corresponds to the line where the angle between the straight line is equal to the angle of rotation. Second, the extraction rotation method Rotation method is When a drawing has the characteristics of an equal segment of “common end and its angle is a special angle ”, a part of the figure or figure may be wound