# Find the general solution of the system of ODE $X'=\begin{bmatrix} 1 & 3 \\ -3 & 1 \end{bmatrix} X$

Find the general solution of the system of ODE
$$X'=\begin{bmatrix} 1 & 3 \\ -3 & 1 \end{bmatrix} X.$$

The final solution should be in real form and does not involve any complex numbers.

Answers can be viewed only if
1. The questioner was satisfied and accepted the answer, or
2. The answer was disputed, but the judge evaluated it as 100% correct.