论文部分内容阅读
非常一:知识回顾 1．直线、线段、射线的概念直线是向两个方向无限延伸着的;直线上两个点和它们之间的部分叫做线段;直线上的一点和它一旁的部分叫做射线． 2．角的定义 (1)有公共端点的两条射线组成的图形叫做角．(2)一条射线由原来位置绕着它的端点旋转到另一个位置所成的图形也叫做角． 3．平角、周角和直角的概念平角:射线OA绕端点O旋转,当终止位置OB与起始位置OA成一条直线时,所成的角叫做平角．周角:射线OA绕端点O旋转,当终止位置OB与起始位置OA第一次重合时所成的角叫做周角．直角:平角的一
Very one: knowledge review 1. The straight line, the line segment, and the concept line of rays are infinitely extended in two directions; the two points on the line and the part between them are called line segments; the point on the line and the line on the line are called rays. 2. Definition of angles (1) A graph consisting of two rays with common endpoints is called a corner. (2) A graph of a ray that is rotated from its original position around its end to another position is also known as the angle. 3. The concept of flat angle, corner angle and right angle: Flat ray: The ray OA rotates around the endpoint O. When the terminating position OB is aligned with the starting position OA, the resulting angle is called the flat angle. Week angle: The ray OA rotates around the endpoint O. The angle formed when the end position OB coincides with the start position OA for the first time is called the corner angle. Right angle: One of the flat angle