83.23.20 problem 20

Internal problem ID [19301]
Book : A Text book for differentional equations for postgraduate students by Ray and Chaturvedi. First edition, 1958. BHASKAR press. INDIA
Section : Chapter V. Singular solutions. Exercise V at page 76
Problem number : 20
Date solved : Tuesday, January 28, 2025 at 01:25:15 PM
CAS classification : [[_homogeneous, `class G`]]

\begin{align*} y+x^{2}&={y^{\prime }}^{2} \end{align*}

Solution by Maple

Time used: 0.039 (sec). Leaf size: 271

dsolve(x^2+y(x)=diff(y(x),x)^2,y(x), singsol=all)
 
\begin{align*} -17 \ln \left (-x^{4}-x^{2} y \left (x \right )+4 y \left (x \right )^{2}\right )-17 \ln \left (-x \sqrt {x^{2}+y \left (x \right )}+2 y \left (x \right )\right )+17 \ln \left (x \sqrt {x^{2}+y \left (x \right )}+2 y \left (x \right )\right )+\left (2 \,\operatorname {arctanh}\left (\frac {\left (4 \sqrt {x^{2}+y \left (x \right )}+x \right ) \sqrt {17}}{17 x}\right )-2 \,\operatorname {arctanh}\left (\frac {\left (x^{2}-8 y \left (x \right )\right ) \sqrt {17}}{17 x^{2}}\right )-2 \,\operatorname {arctanh}\left (\frac {\left (x -4 \sqrt {x^{2}+y \left (x \right )}\right ) \sqrt {17}}{17 x}\right )\right ) \sqrt {17}-c_{1} &= 0 \\ 17 \ln \left (-x^{4}-x^{2} y \left (x \right )+4 y \left (x \right )^{2}\right )-17 \ln \left (-x \sqrt {x^{2}+y \left (x \right )}+2 y \left (x \right )\right )+17 \ln \left (x \sqrt {x^{2}+y \left (x \right )}+2 y \left (x \right )\right )+\left (2 \,\operatorname {arctanh}\left (\frac {\left (4 \sqrt {x^{2}+y \left (x \right )}+x \right ) \sqrt {17}}{17 x}\right )+2 \,\operatorname {arctanh}\left (\frac {\left (x^{2}-8 y \left (x \right )\right ) \sqrt {17}}{17 x^{2}}\right )-2 \,\operatorname {arctanh}\left (\frac {\left (x -4 \sqrt {x^{2}+y \left (x \right )}\right ) \sqrt {17}}{17 x}\right )\right ) \sqrt {17}-c_{1} &= 0 \\ \end{align*}

Solution by Mathematica

Time used: 1.239 (sec). Leaf size: 215

DSolve[x^2+y[x]==D[y[x],x]^2,y[x],x,IncludeSingularSolutions -> True]
 
\begin{align*} \text {Solve}\left [\frac {1}{34} \left (-34 \log \left (\sqrt {x^2+y(x)}-x\right )-\left (\sqrt {17}-17\right ) \log \left (2 x \sqrt {x^2+y(x)}-2 x^2-\sqrt {17} y(x)+3 y(x)\right )+\left (17+\sqrt {17}\right ) \log \left (2 x \sqrt {x^2+y(x)}-2 x^2+\left (3+\sqrt {17}\right ) y(x)\right )\right )&=c_1,y(x)\right ] \\ \text {Solve}\left [\frac {1}{34} \left (-34 \log \left (\sqrt {x^2+y(x)}-x\right )+\left (17+\sqrt {17}\right ) \log \left (2 x \sqrt {x^2+y(x)}-2 x^2+\left (\sqrt {17}-5\right ) y(x)\right )-\left (\sqrt {17}-17\right ) \log \left (2 x \sqrt {x^2+y(x)}-2 x^2-\left (5+\sqrt {17}\right ) y(x)\right )\right )&=c_1,y(x)\right ] \\ \end{align*}