19.4 problem 4

Internal problem ID [14896]

Book: INTRODUCTORY DIFFERENTIAL EQUATIONS. Martha L. Abell, James P. Braselton. Fourth edition 2014. ElScAe. 2014
Section: Chapter 5. Applications of Higher Order Equations. Exercises 5.1, page 232
Problem number: 4.
ODE order: 2.
ODE degree: 1.

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

\[ \boxed {x^{\prime \prime }+100 x=0} \] With initial conditions \begin {align*} \left [x \left (0\right ) = -{\frac {1}{4}}, x^{\prime }\left (0\right ) = 1\right ] \end {align*}

Solution by Maple

Time used: 0.016 (sec). Leaf size: 17

dsolve([diff(x(t),t$2)+100*x(t)=0,x(0) = -1/4, D(x)(0) = 1],x(t), singsol=all)
 

\[ x \left (t \right ) = \frac {\sin \left (10 t \right )}{10}-\frac {\cos \left (10 t \right )}{4} \]

Solution by Mathematica

Time used: 0.014 (sec). Leaf size: 22

DSolve[{x''[t]+100*x[t]==0,{x[0]==-1/4,x'[0]==1}},x[t],t,IncludeSingularSolutions -> True]
 

\[ x(t)\to \frac {1}{20} (2 \sin (10 t)-5 \cos (10 t)) \]