4.5 problem Problem 13

Internal problem ID [2160]

Book: Differential equations and linear algebra, Stephen W. Goode and Scott A Annin. Fourth edition, 2015
Section: Chapter 1, First-Order Differential Equations. Section 1.8, Change of Variables. page 79
Problem number: Problem 13.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [[_homogeneous, class A], _rational, _dAlembert]

Solve \begin {gather*} \boxed {y^{\prime } x -\sqrt {16 x^{2}-y^{2}}-y=0} \end {gather*}

Solution by Maple

Time used: 0.019 (sec). Leaf size: 29

dsolve(x*diff(y(x),x)=sqrt(16*x^2-y(x)^2)+y(x),y(x), singsol=all)
 

\[ -\arctan \left (\frac {y \relax (x )}{\sqrt {16 x^{2}-y \relax (x )^{2}}}\right )+\ln \relax (x )-c_{1} = 0 \]

Solution by Mathematica

Time used: 0.368 (sec). Leaf size: 18

DSolve[x*y'[x]==Sqrt[16*x^2-y[x]^2]+y[x],y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to -4 x \cosh (i \log (x)+c_1) \\ \end{align*}