Solution by Integrating Factor/Examples

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Examples of Use of Solution by Integrating Factor

Example: $y' - 3 y = \sin x$

The linear first order ODE:

$\dfrac {\d y} {\d x} - 3 y = \sin x$

has the general solution:

$y = \dfrac 1 {10} \paren {3 \sin x - \cos x} + C e^{3 x}$


Example: $y' + y = \dfrac 1 x$

Consider the linear first order ODE:

$(1): \quad \dfrac {\d y} {\d x} + y = \dfrac 1 x$

with the initial condition $\tuple {1, 0}$.

This has the particular solution:

$y = \ds e^{-x} \int_1^x \dfrac {e^\xi \rd \xi} \xi$