7.2 Linear ode with non-constant coefficients

7.2.1 Euler type \(x^{3}y^{\prime \prime \prime }+x^{2}y^{\prime \prime }+xy^{\prime }+y=f\left ( x\right ) \)
7.2.2 Solved using reduction of order
7.2.3 Examples
7.2.4 Solved by finding first intergal (applies to exact ode only)
7.2.5 Solved by series method