項(xiàng)東 沈燕

摘 要：數(shù)學(xué)學(xué)習(xí)在于思維訓(xùn)練。依次連接三角形頂點(diǎn)和對(duì)邊中點(diǎn)的三中線向量可構(gòu)成三角形，依次連接三角形頂點(diǎn)和對(duì)邊上的點(diǎn)的向量什么情況下能構(gòu)成三角形？這三角形與原三角形有何關(guān)系？四邊形是否也有相似性質(zhì)。

關(guān)鍵詞：向量；向量三角形法則；三角形；空間四邊形

Thinking and exploration of polygon formation based on vector triangle rule

XIANG Dong SHEN Yan

（Jiaxing University of Normal College Jiaxing 314200）

Abstract：Mathematics learning consists in thinking training.A triangle can be formed by conn-ecting three midline vectors that connect the vertices of a triangle to the midpoint of the opposite

side. Under what conditions can a triangle be formed by connecting the vertices of a triangle to th-e midpoint of the opposite side？How does this triangle relate to the original triangle triangle？Does the quadrilateral have similar properties.

Keywords：Vector； Vector triangle rule； Triangle； Space quadrilateral