许多报刊杂志上对三角形在四面体中的类比作了详尽的阐述.事实上,由三角形的一些重要定理也能类比得到三棱柱的许多相似的重要定理.笔者对此作了一些浅探,以揭示平面图形与空间图形的内在联系及和谐统一的数学美.为了下文叙述和书写的方便,设三棱柱ABC-A1B1C1的侧棱长为l,侧面A Many newspapers and magazines have elaborated on the analogy of triangles in tetrahedrons. In fact, some important theorems of triangles can also be compared to obtain many similar important theorems of trigonal prisms. The author has made some brief explorations. Reveal the intrinsic connection between the plane graphics and the spatial graphics and the harmonious and unified mathematics beauty. For the convenience of the following narrative and writing, set the side prism of the triangular prism ABC-A1B1C1 to length l, side A