On a Solution of the Quaternion Matrix Equation {A \tilde{X} -X B = C} and Its Applications

This paper studies the problem of solution of the quaternion matrix equation ${A \tilde{X} -X B = C}$ by means of real representation of a quaternion matrix, derives a similarity version of Roth’s theorem for the existence of solution to the quaternion matrix equation, and obtains closed-form solutions of the quaternion matrix equation in explicit forms. As a special case, this paper also gives some applications of the solutions of complex matrix equation ${A \bar{X} -X B = C}$ and of the consimilarity of complex matrices.