1. The problem involves solving the system of differential equations:
$$Dx - 4y = 1$$
$$x + Dy = 2$$
where $D$ denotes differentiation with respect to $t$.
2. From the first equation, express $y$ in terms of $x$ and its derivatives:
$$y = \frac{1}{4}Dx - \frac{1}{4}$$
3. Substitute $y$ into the second equation:
$$x + D\left(\frac{1}{4}Dx - \frac{1}{4}\right) = 2$$
4. Simplify the derivative:
$$x + \frac{1}{4}D^2x - 0 = 2$$
which gives
$$(D^2 + 1)x = 2$$
5. This is a nonhomogeneous second-order linear differential equation. The complementary (homogeneous) equation is:
$$(D^2 + 1)x = 0$$
with characteristic equation:
$$r^2 + 1 = 0 \implies r = \pm i$$
6. The general solution to the homogeneous equation is:
$$x_h = c_1 \cos t + c_2 \sin t$$
7. For the particular solution $x_p$, since the right side is constant 2, try a constant solution:
$$x_p = A$$
Substitute into the equation:
$$(0 + 1)A = 2 \implies A = 2$$
8. Therefore, the general solution for $x$ is:
$$x = c_1 \cos t + c_2 \sin t + 2$$
9. Substitute $x$ back into the expression for $y$:
$$y = \frac{1}{4}Dx - \frac{1}{4} = \frac{1}{4}\left(-c_1 \sin t + c_2 \cos t\right) - \frac{1}{4}$$
10. Simplify $y$:
$$y = -\frac{1}{4} c_1 \sin t + \frac{1}{4} c_2 \cos t - \frac{1}{4}$$
Thus, the solutions are:
$$x = c_1 \cos t + c_2 \sin t + 2$$
$$y = -\frac{1}{4} c_1 \sin t + \frac{1}{4} c_2 \cos t - \frac{1}{4}$$
This completes the solution.
Differential System A1F632
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.