Matrix exponentiation

In mathematics, the matrix exponential is a matrix function on square matrices analogous to the ordinary exponential function. It is used to solve systems of linear differential equations. In the theory of Lie groups, the matrix exponential gives the connection between a matrix Lie algebra and the corresponding Lie group.

Let X be an n×n real or complex matrix. The exponential of X, denoted by e^X or exp(X), is the n×n matrix given by the power series

where ${\displaystyle X^{0}}$ is defined to be the identity matrix ${\displaystyle I}$ with the same dimensions as ${\displaystyle X}$.

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