Some properties of the optimal path of trust region methods are shown, and the relationship between dogleg path and optimal path is analysed.This can be used to derive better approximate algorithms for solving trust region subproblems.

• 本文描述了信赖域方法最优曲线在二维子空间内投影的几个性质，分析了几种信赖域折线法与该投影的关系，为推导更好的求解信赖域子问题的折线近似提供理论依据.