79.1.20 problem 4 (ii)

Internal problem ID [18507]
Book : Elementary Differential Equations. By R.L.E. Schwarzenberger. Chapman and Hall. London. First Edition (1969)
Section : Chapter 3. Solutions of first-order equations. Exercises at page 47
Problem number : 4 (ii)
Date solved : Tuesday, January 28, 2025 at 11:51:24 AM
CAS classification : [_separable]

\begin{align*} x^{\prime }+x \tan \left (t \right )&=0 \end{align*}

✓ Solution by Maple

Time used: 0.002 (sec). Leaf size: 8

dsolve(diff(x(t),t)+x(t)*tan(t)=0,x(t), singsol=all)
 

\[ x = c_{1} \cos \left (t \right ) \]

✓ Solution by Mathematica

Time used: 0.032 (sec). Leaf size: 15

DSolve[D[x[t],t]+x[t]*Tan[t]==0,x[t],t,IncludeSingularSolutions -> True]
 

\begin{align*} x(t)\to c_1 \cos (t) \\ x(t)\to 0 \\ \end{align*}