角平分线定义（Angle bisector definition） 从一个角的顶点引出一条射线，把这个角分成两个完全相同的角，这条射线叫做这个角的角平分线。 三角形三条角平分线的交点叫做三角形的内心。三角形的内心到三边的距离相等，是该三角形内切圆的圆心。
一种角平分线绘制器，它由四条连杆铰接组成的菱形框架构成。
The utility model relates to an angle bisector drawing instrument which consists of a rhombus-shaped frame formed by articulating four connecting bars.
通过对角平分线投影特性的分析、总结，从理论上证明了角平分线投影特性。
The analysis and summarization, the projection character of Angle bisector is proved on theory.
解决一追二问题的方法共讨论了三种：初始角的平分线航向法、瞬时角的平分线航向法、中点轨迹法。
Three methods are discussed to solve the one pursue two problem, they are course method of the initial angular bisector, course method of the instantaneous angular bisector and mid-point path method.
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