10.6.21 problem 21

Internal problem ID [1238]
Book : Elementary differential equations and boundary value problems, 10th ed., Boyce and DiPrima
Section : Miscellaneous problems, end of chapter 2. Page 133
Problem number : 21
Date solved : Monday, January 27, 2025 at 04:47:08 AM
CAS classification : [_rational]

\begin{align*} \frac {-4+6 y x +2 y^{2}}{3 x^{2}+4 y x +3 y^{2}}+y^{\prime }&=0 \end{align*}

Solution by Maple

Time used: 0.013 (sec). Leaf size: 513

dsolve((-4+6*x*y(x)+2*y(x)^2)/(3*x^2+4*x*y(x)+3*y(x)^2)+diff(y(x),x)=0,y(x), singsol=all)
 
\begin{align*} y &= \frac {\left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{1}/{3}}}{6}-\frac {10 x^{2}}{3 \left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{1}/{3}}}-\frac {2 x}{3} \\ y &= -\frac {\left (1+i \sqrt {3}\right ) \left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{1}/{3}}}{12}-\frac {5 x \left (i \sqrt {3}\, x -x +\frac {2 \left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{1}/{3}}}{5}\right )}{3 \left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{1}/{3}}} \\ y &= \frac {i \sqrt {3}\, \left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{2}/{3}}+20 i \sqrt {3}\, x^{2}-\left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{2}/{3}}-8 x \left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{1}/{3}}+20 x^{2}}{12 \left (152 x^{3}-108 c_1 +432 x +12 \sqrt {216 x^{6}-228 c_1 \,x^{3}+912 x^{4}+81 c_1^{2}-648 c_1 x +1296 x^{2}}\right )^{{1}/{3}}} \\ \end{align*}

Solution by Mathematica

Time used: 4.888 (sec). Leaf size: 383

DSolve[(-4+6*x*y[x]+2*y[x]^2)/(3*x^2+4*x*y[x]+3*y[x]^2)+D[y[x],x]==0,y[x],x,IncludeSingularSolutions -> True]
 
\begin{align*} y(x)\to \frac {1}{6} \left (2^{2/3} \sqrt [3]{38 x^3+\sqrt {500 x^6+\left (38 x^3+108 x+27 c_1\right ){}^2}+108 x+27 c_1}-\frac {10 \sqrt [3]{2} x^2}{\sqrt [3]{38 x^3+\sqrt {500 x^6+\left (38 x^3+108 x+27 c_1\right ){}^2}+108 x+27 c_1}}-4 x\right ) \\ y(x)\to \frac {1}{12} \left (i 2^{2/3} \left (\sqrt {3}+i\right ) \sqrt [3]{38 x^3+\sqrt {500 x^6+\left (38 x^3+108 x+27 c_1\right ){}^2}+108 x+27 c_1}+\frac {10 \sqrt [3]{2} \left (1+i \sqrt {3}\right ) x^2}{\sqrt [3]{38 x^3+\sqrt {500 x^6+\left (38 x^3+108 x+27 c_1\right ){}^2}+108 x+27 c_1}}-8 x\right ) \\ y(x)\to \frac {1}{12} \left (-2^{2/3} \left (1+i \sqrt {3}\right ) \sqrt [3]{38 x^3+\sqrt {500 x^6+\left (38 x^3+108 x+27 c_1\right ){}^2}+108 x+27 c_1}+\frac {10 \sqrt [3]{2} \left (1-i \sqrt {3}\right ) x^2}{\sqrt [3]{38 x^3+\sqrt {500 x^6+\left (38 x^3+108 x+27 c_1\right ){}^2}+108 x+27 c_1}}-8 x\right ) \\ \end{align*}