In the paper we give solid commulative diagram of short exact sequences induced by product αβγof morphisms.
本文给出了Ａｂｅｌ范畴中态射乘积αβγ诱导的短正合列的立体交换图。
In this paper, we study modules and short exact sequences over two kinds of 2×2 matrix rings.
文章讨论了两类二阶矩阵环上的模及其短正合列,得到环R上的短正合列在两类矩阵环的自然推广形式。