First order linear ordinary differential equations in associative algebras

In this paper, we study the linear differential equation $$ frac{dx}{dt}=sum_{i=1}^n a_i(t) x b_i(t) + f(t) $$ in an associative but non-commutative algebra $mathcal{A}$, where the $b_i(t)$ form a set of commuting $mathcal{A}$-valued functions expressed in a time-independent spectral basis consisting of mutually annihilating idempotents and nilpotents. Explicit new closed solutions are derived, and examples are presented to illustrate the theory.