Internal problem ID [11294]
Book: An elementary treatise on differential equations by Abraham Cohen. DC heath publishers.
1906
Section: Chapter VII, Linear differential equations with constant coefficients. Article 52.
Summary. Page 117
Problem number: Ex 10.
ODE order: 2.
ODE degree: 1.
CAS Maple gives this as type [[_2nd_order, _linear, _nonhomogeneous]]
\[ \boxed {y^{\prime \prime }+4 y=\sec \left (x \right )^{2}} \]
✓ Solution by Maple
Time used: 0.015 (sec). Leaf size: 42
dsolve(diff(y(x),x$2)+4*y(x)=sec(x)^2,y(x), singsol=all)
\[ y \left (x \right ) = \sin \left (2 x \right ) c_{2} +\cos \left (2 x \right ) c_{1} +\left (-2 \cos \left (x \right )^{2}+1\right ) \ln \left (\sec \left (x \right )\right )+2 x \cos \left (x \right ) \sin \left (x \right )-\sin \left (x \right )^{2} \]
✓ Solution by Mathematica
Time used: 0.168 (sec). Leaf size: 33
DSolve[y''[x]+4*y[x]==Sec[x]^2,y[x],x,IncludeSingularSolutions -> True]
\[ y(x)\to \cos (2 x) (\log (\cos (x))+c_1)+\sin (x) (-\sin (x)+2 (x+c_2) \cos (x)) \]