幂等

This paper is a study on the invertibility of the commutator of scalar-idempotent elements and scalar-involutory elements of a unitary ring.

本文研究在一个有单位元的环中个倍幂等元的换位个倍对合元的换位的可逆性问题。

The necessary and sufficient conditions of similarity of two idempotent matrices are proved, the idempotency of linear combinations of two idempotent matrices is discussed.

摘要证明数域上个同阶幂等阵似的充要条件是它有同的秩；给出幂等阵的似标准型；讨论个幂等阵的线性组合仍是幂等阵的充要条件。