设P是△ABC所在平面内任意一点，AP，BP，CP交直线BC，CA，AB分别于D，E，F，则称△DEF为点P关联△ABC的内接三角形．本文得到了此类内接△DEF与△ABC面积关系的统一公式．即定理设P是△ABC所在平面内的一点，△DEF是P关联△ABC的内接三角形，若有向线段的比，则有Ceva定理知2l Let P be any point in the plane of △ABC, AP, BP, CP intersect the line BC, CA, AB respectively in D, E, F, then call △DEF as the point P associated with △ ABC intrinsic triangle. In this paper, we obtain a unified formula for the relationship between the area of ​​intrinsic △DEF and △ABC. That is, the theorem establishes that P is a point in the plane of △ABC, △DEF is the intrinsic triangle of P-correlation △ABC, if there is a ratio of line segments, there is Ceva’s theorem 2l