Solution by Integrating Factor/Examples/y' - 3y = sin x

Theorem
The linear first order ODE:
 * $\dfrac {\d y} {\d x} - 3 y = \sin x$

has the general solution:
 * $y = \dfrac 1 {10} \paren {3 \sin x - \cos x} + C e^{3 x}$