74.12.4 problem 4

Internal problem ID [16311]
Book : INTRODUCTORY DIFFERENTIAL EQUATIONS. Martha L. Abell, James P. Braselton. Fourth edition 2014. ElScAe. 2014
Section : Chapter 4. Higher Order Equations. Exercises 4.4, page 163
Problem number : 4
Date solved : Tuesday, January 28, 2025 at 09:02:39 AM
CAS classification : [[_2nd_order, _linear, _nonhomogeneous]]

\begin{align*} y^{\prime \prime }+16 y&=2 \cos \left (4 t \right ) \end{align*}

Solution by Maple

Time used: 0.003 (sec). Leaf size: 27

dsolve(diff(y(t),t$2)+16*y(t)=2*cos(4*t),y(t), singsol=all)
 
\[ y = \frac {\left (16 c_{1} +1\right ) \cos \left (4 t \right )}{16}+\frac {\left (t +4 c_{2} \right ) \sin \left (4 t \right )}{4} \]

Solution by Mathematica

Time used: 0.041 (sec). Leaf size: 64

DSolve[D[y[t],{t,2}]+16*y[t]==2*Cos[4*t],y[t],t,IncludeSingularSolutions -> True]
 
\[ y(t)\to \sin (4 t) \int _1^t\frac {1}{2} \cos ^2(4 K[2])dK[2]+\cos (4 t) \int _1^t-\frac {1}{4} \sin (8 K[1])dK[1]+c_1 \cos (4 t)+c_2 \sin (4 t) \]