Matrix and determinant are essential concepts which is used to solve linear equations.This paper mainly considers the application of generalized orthogonal matrices and determinant of matrices over a commutative semiring.We first discuss some properties of generalized orthogonal matrices and their equivalent characterization under some additional conditions.And second,we obtain some necessary and sufficient conditions for which a standard orthogonal set can be extended to a standard orthogonal basis in a finitely generated semimodule over a commutative semiring.Then,the properties of determinants of matrices are given,and some necessary and sufficient conditions that a system of linear equation is solvable with certain conditions are studied.At last,we show that the Cramer's rule over a commutative semiring is valid.This paper is organized as follows:In Chapter 1,some basic concepts and related conclusions of semirings are reviewed.In Chapter 2,we first study the properties of generalized orthogonal matrices over a commutative semiring and their equivalent characterization under some additional conditions,then some necessary and sufficient conditions that a standard orthogonal set can be extended to a standard orthogonal basis in a finitely generated semimodule over a commutative semiring are obtained.In Chapter 3,we investigate some properties of the determinant of a matrix over a commutative semiring and give some necessary and sufficient conditions that a system of linear equation is solvable with certain conditions.It finally shows that the Cramer's rule is valid. |