60.2.45 problem 621

Internal problem ID [10632]
Book : Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section : Chapter 1, Additional non-linear first order
Problem number : 621
Date solved : Monday, January 27, 2025 at 09:18:51 PM
CAS classification : [[_homogeneous, `class G`], [_Abel, `2nd type`, `class C`]]

\begin{align*} y^{\prime }&=\frac {1}{y+\sqrt {x}} \end{align*}

Solution by Maple

Time used: 4.937 (sec). Leaf size: 59

dsolve(diff(y(x),x) = 1/(y(x)+x^(1/2)),y(x), singsol=all)
 
\[ y = \frac {\operatorname {RootOf}\left (\textit {\_Z}^{18} c_{1} -9 x \,\textit {\_Z}^{6}-6 \textit {\_Z}^{3} \sqrt {x}-1\right )^{3} \sqrt {x}+1}{\operatorname {RootOf}\left (\textit {\_Z}^{18} c_{1} -9 x \,\textit {\_Z}^{6}-6 \textit {\_Z}^{3} \sqrt {x}-1\right )^{3}} \]

Solution by Mathematica

Time used: 60.046 (sec). Leaf size: 445

DSolve[D[y[x],x] == (Sqrt[x] + y[x])^(-1),y[x],x,IncludeSingularSolutions -> True]
 
\begin{align*} y(x)\to -\sqrt {x}+\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 x^3+16 e^{12 c_1}\right )-24 \text {$\#$1}^4 x^2+8 \text {$\#$1}^3 x^{3/2}+9 \text {$\#$1}^2 x-6 \text {$\#$1} \sqrt {x}+1\&,1\right ]} \\ y(x)\to -\sqrt {x}+\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 x^3+16 e^{12 c_1}\right )-24 \text {$\#$1}^4 x^2+8 \text {$\#$1}^3 x^{3/2}+9 \text {$\#$1}^2 x-6 \text {$\#$1} \sqrt {x}+1\&,2\right ]} \\ y(x)\to -\sqrt {x}+\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 x^3+16 e^{12 c_1}\right )-24 \text {$\#$1}^4 x^2+8 \text {$\#$1}^3 x^{3/2}+9 \text {$\#$1}^2 x-6 \text {$\#$1} \sqrt {x}+1\&,3\right ]} \\ y(x)\to -\sqrt {x}+\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 x^3+16 e^{12 c_1}\right )-24 \text {$\#$1}^4 x^2+8 \text {$\#$1}^3 x^{3/2}+9 \text {$\#$1}^2 x-6 \text {$\#$1} \sqrt {x}+1\&,4\right ]} \\ y(x)\to -\sqrt {x}+\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 x^3+16 e^{12 c_1}\right )-24 \text {$\#$1}^4 x^2+8 \text {$\#$1}^3 x^{3/2}+9 \text {$\#$1}^2 x-6 \text {$\#$1} \sqrt {x}+1\&,5\right ]} \\ y(x)\to -\sqrt {x}+\frac {1}{\text {Root}\left [\text {$\#$1}^6 \left (16 x^3+16 e^{12 c_1}\right )-24 \text {$\#$1}^4 x^2+8 \text {$\#$1}^3 x^{3/2}+9 \text {$\#$1}^2 x-6 \text {$\#$1} \sqrt {x}+1\&,6\right ]} \\ \end{align*}