26.2.10 problem 10

Internal problem ID [4259]
Book : Differential equations with applications and historial notes, George F. Simmons. Second edition. 1971
Section : Chapter 2, section 8, page 41
Problem number : 10
Date solved : Monday, January 27, 2025 at 08:46:03 AM
CAS classification : [_exact, [_1st_order, `_with_symmetry_[F(x),G(x)*y+H(x)]`]]

\begin{align*} 2 x y^{3}+y \cos \left (x \right )+\left (3 x^{2} y^{2}+\sin \left (x \right )\right ) y^{\prime }&=0 \end{align*}

Solution by Maple

Time used: 0.005 (sec). Leaf size: 298

dsolve((2*x*y(x)^3+y(x)*cos(x))+(3*x^2*y(x)^2+sin(x))*diff(y(x),x)=0,y(x), singsol=all)
 
\begin{align*} y \left (x \right ) &= \frac {\left (12 \sqrt {3}\, \sqrt {27 c_{1}^{2} x^{2}+4 \sin \left (x \right )^{3}}-108 c_{1} x \right )^{{2}/{3}}-12 \sin \left (x \right )}{6 x \left (12 \sqrt {3}\, \sqrt {27 c_{1}^{2} x^{2}+4 \sin \left (x \right )^{3}}-108 c_{1} x \right )^{{1}/{3}}} \\ y \left (x \right ) &= -\frac {i \sqrt {3}\, \left (12 \sqrt {3}\, \sqrt {27 c_{1}^{2} x^{2}+4 \sin \left (x \right )^{3}}-108 c_{1} x \right )^{{2}/{3}}+12 i \sin \left (x \right ) \sqrt {3}+\left (12 \sqrt {3}\, \sqrt {27 c_{1}^{2} x^{2}+4 \sin \left (x \right )^{3}}-108 c_{1} x \right )^{{2}/{3}}-12 \sin \left (x \right )}{12 x \left (12 \sqrt {3}\, \sqrt {27 c_{1}^{2} x^{2}+4 \sin \left (x \right )^{3}}-108 c_{1} x \right )^{{1}/{3}}} \\ y \left (x \right ) &= \frac {i \sqrt {3}\, \left (12 \sqrt {3}\, \sqrt {27 c_{1}^{2} x^{2}+4 \sin \left (x \right )^{3}}-108 c_{1} x \right )^{{2}/{3}}+12 i \sin \left (x \right ) \sqrt {3}-\left (12 \sqrt {3}\, \sqrt {27 c_{1}^{2} x^{2}+4 \sin \left (x \right )^{3}}-108 c_{1} x \right )^{{2}/{3}}+12 \sin \left (x \right )}{12 x \left (12 \sqrt {3}\, \sqrt {27 c_{1}^{2} x^{2}+4 \sin \left (x \right )^{3}}-108 c_{1} x \right )^{{1}/{3}}} \\ \end{align*}

Solution by Mathematica

Time used: 31.272 (sec). Leaf size: 339

DSolve[(2*x*y[x]^3+y[x]*Cos[x])+(3*x^2*y[x]^2+Sin[x])*D[y[x],x]==0,y[x],x,IncludeSingularSolutions -> True]
 
\begin{align*} y(x)\to \frac {\sqrt [3]{9 c_1 x^4+\sqrt {12 x^6 \sin ^3(x)+81 c_1{}^2 x^8}}}{\sqrt [3]{2} 3^{2/3} x^2}-\frac {\sqrt [3]{\frac {2}{3}} \sin (x)}{\sqrt [3]{9 c_1 x^4+\sqrt {12 x^6 \sin ^3(x)+81 c_1{}^2 x^8}}} \\ y(x)\to \frac {\left (1+i \sqrt {3}\right ) \sin (x)}{2^{2/3} \sqrt [3]{27 c_1 x^4+3 \sqrt {12 x^6 \sin ^3(x)+81 c_1{}^2 x^8}}}-\frac {\left (1-i \sqrt {3}\right ) \sqrt [3]{27 c_1 x^4+\sqrt {108 x^6 \sin ^3(x)+729 c_1{}^2 x^8}}}{6 \sqrt [3]{2} x^2} \\ y(x)\to \frac {\left (1-i \sqrt {3}\right ) \sin (x)}{2^{2/3} \sqrt [3]{27 c_1 x^4+3 \sqrt {12 x^6 \sin ^3(x)+81 c_1{}^2 x^8}}}-\frac {\left (1+i \sqrt {3}\right ) \sqrt [3]{27 c_1 x^4+\sqrt {108 x^6 \sin ^3(x)+729 c_1{}^2 x^8}}}{6 \sqrt [3]{2} x^2} \\ \end{align*}