4.3 Linear second order ode

4.3.1 Linear ode with constant coefficients \(Ay^{\prime \prime }+By^{\prime }+Cy=f\left ( x\right ) \)
4.3.2 Linear ode with non-constant coefficients \(A\left ( x\right ) y^{\prime \prime }+B\left ( x\right ) y^{\prime }+C\left ( x\right ) y=f\left ( x\right ) \)