3.422 problem 1423

Internal problem ID [9002]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 2, linear second order
Problem number: 1423.
ODE order: 2.
ODE degree: 1.

CAS Maple gives this as type [[_2nd_order, _with_linear_symmetries]]

Solve \begin {gather*} \boxed {y^{\prime \prime }+\frac {a y}{\sin \relax (x )^{2}}=0} \end {gather*}

Solution by Maple

Time used: 0.156 (sec). Leaf size: 165

dsolve(diff(diff(y(x),x),x) = -a/sin(x)^2*y(x),y(x), singsol=all)
 

\[ y \relax (x ) = \frac {c_{1} \left (2 \cos \left (2 x \right )+2\right )^{\frac {1}{4}} \hypergeom \left (\left [\frac {\sqrt {1-4 a}}{4}+\frac {1}{4}, \frac {\sqrt {1-4 a}}{4}+\frac {1}{4}\right ], \left [\frac {1}{2}\right ], \frac {\cos \left (2 x \right )}{2}+\frac {1}{2}\right ) \sqrt {-2 \cos \left (2 x \right )+2}\, \left (\frac {\cos \left (2 x \right )}{2}-\frac {1}{2}\right )^{\frac {\sqrt {1-4 a}}{4}}}{\sqrt {\sin \left (2 x \right )}}+\frac {c_{2} \left (2 \cos \left (2 x \right )+2\right )^{\frac {3}{4}} \hypergeom \left (\left [\frac {\sqrt {1-4 a}}{4}+\frac {3}{4}, \frac {\sqrt {1-4 a}}{4}+\frac {3}{4}\right ], \left [\frac {3}{2}\right ], \frac {\cos \left (2 x \right )}{2}+\frac {1}{2}\right ) \sqrt {-2 \cos \left (2 x \right )+2}\, \left (\frac {\cos \left (2 x \right )}{2}-\frac {1}{2}\right )^{\frac {\sqrt {1-4 a}}{4}}}{\sqrt {\sin \left (2 x \right )}} \]

Solution by Mathematica

Time used: 0.042 (sec). Leaf size: 61

DSolve[y''[x] == -(a*Csc[x]^2*y[x]),y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \sqrt [4]{-\sin ^2(x)} \left (c_1 P_{-\frac {1}{2}}^{\frac {1}{2} \sqrt {1-4 a}}(\cos (x))+c_2 Q_{-\frac {1}{2}}^{\frac {1}{2} \sqrt {1-4 a}}(\cos (x))\right ) \\ \end{align*}