1.94 problem 116

Internal problem ID [2730]

Book: Differential equations for engineers by Wei-Chau XIE, Cambridge Press 2010
Section: Chapter 2. First-Order and Simple Higher-Order Differential Equations. Page 78
Problem number: 116.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_exact, _Bernoulli]

Solve \begin {gather*} \boxed {1+y^{2} \sin \left (2 x \right )-2 y \left (\cos ^{2}\relax (x )\right ) y^{\prime }=0} \end {gather*}

Solution by Maple

Time used: 0.0 (sec). Leaf size: 28

dsolve((1+y(x)^2*sin(2*x))-(2*y(x)*cos(x)^2)*diff(y(x),x)=0,y(x), singsol=all)
 

\begin{align*} y \relax (x ) = \frac {\sqrt {x +c_{1}}}{\cos \relax (x )} \\ y \relax (x ) = -\frac {\sqrt {x +c_{1}}}{\cos \relax (x )} \\ \end{align*}

Solution by Mathematica

Time used: 0.33 (sec). Leaf size: 32

DSolve[(1+y[x]^2*Sin[2*x])-(2*y[x]*Cos[x]^2)*y'[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to -\sqrt {x+c_1} \sec (x) \\ y(x)\to \sqrt {x+c_1} \sec (x) \\ \end{align*}