1.322 problem 323

Internal problem ID [8659]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, linear first order
Problem number: 323.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_rational]

\[ \boxed {\left (a x y^{3}+c \right ) x y^{\prime }+\left (b \,x^{3} y+c \right ) y=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 761

dsolve((a*x*y(x)^3+c)*x*diff(y(x),x)+(b*x^3*y(x)+c)*y(x) = 0,y(x), singsol=all)
 

\begin{align*} y \left (x \right ) = \frac {{\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}{3 a x}+\frac {\left (-b \,x^{2}+2 c_{1} \right ) x}{{\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}} y \left (x \right ) = -\frac {{\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}{6 a x}-\frac {\left (-b \,x^{2}+2 c_{1} \right ) x}{2 {\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}-\frac {i \sqrt {3}\, \left (\frac {{\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}{3 a x}-\frac {\left (-b \,x^{2}+2 c_{1} \right ) x}{{\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}\right )}{2} y \left (x \right ) = -\frac {{\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}{6 a x}-\frac {\left (-b \,x^{2}+2 c_{1} \right ) x}{2 {\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}+\frac {i \sqrt {3}\, \left (\frac {{\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}{3 a x}-\frac {\left (-b \,x^{2}+2 c_{1} \right ) x}{{\left (\left (27 c +3 \sqrt {-\frac {3 \left (-b^{3} x^{8}+6 b^{2} c_{1} x^{6}-12 b \,c_{1}^{2} x^{4}+8 c_{1}^{3} x^{2}-27 a \,c^{2}\right )}{a}}\right ) a^{2} x^{2}\right )}^{\frac {1}{3}}}\right )}{2} \end{align*}

Solution by Mathematica

Time used: 54.413 (sec). Leaf size: 484

DSolve[y[x]*(c + b*x^3*y[x]) + x*(c + a*x*y[x]^3)*y'[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \frac {x \left (-b x^2+2 c_1\right )}{\sqrt [3]{3} \sqrt [3]{9 a^2 c x^2+\sqrt {3} \sqrt {a^3 x^4 \left (27 a c^2+x^2 \left (b x^2-2 c_1\right ){}^3\right )}}}+\frac {\sqrt [3]{9 a^2 c x^2+\sqrt {3} \sqrt {a^3 x^4 \left (27 a c^2+x^2 \left (b x^2-2 c_1\right ){}^3\right )}}}{3^{2/3} a x} y(x)\to \frac {i \sqrt [3]{3} \left (\sqrt {3}+i\right ) \left (9 a^2 c x^2+\sqrt {3} \sqrt {a^3 x^4 \left (27 a c^2+x^2 \left (b x^2-2 c_1\right ){}^3\right )}\right ){}^{2/3}+\sqrt [6]{3} \left (\sqrt {3}+3 i\right ) a x^2 \left (b x^2-2 c_1\right )}{6 a x \sqrt [3]{9 a^2 c x^2+\sqrt {3} \sqrt {a^3 x^4 \left (27 a c^2+x^2 \left (b x^2-2 c_1\right ){}^3\right )}}} y(x)\to \frac {\sqrt [6]{3} \left (\sqrt {3}-3 i\right ) a x^2 \left (b x^2-2 c_1\right )-i \sqrt [3]{3} \left (\sqrt {3}-i\right ) \left (9 a^2 c x^2+\sqrt {3} \sqrt {a^3 x^4 \left (27 a c^2+x^2 \left (b x^2-2 c_1\right ){}^3\right )}\right ){}^{2/3}}{6 a x \sqrt [3]{9 a^2 c x^2+\sqrt {3} \sqrt {a^3 x^4 \left (27 a c^2+x^2 \left (b x^2-2 c_1\right ){}^3\right )}}} \end{align*}