5.6 problem 2

Internal problem ID [980]

Book: Elementary differential equations with boundary value problems. William F. Trench. Brooks/Cole 2001
Section: Chapter 2, First order equations. Transformation of Nonlinear Equations into Separable Equations. Section 2.4 Page 68
Problem number: 2.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [[_homogeneous, `class G`], _rational, _Bernoulli]

\[ \boxed {7 y^{\prime } x -2 y+\frac {x^{2}}{y^{6}}=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 134

dsolve(7*x*diff(y(x),x)-2*y(x)=-x^2/y(x)^6,y(x), singsol=all)
 

\begin{align*} y \left (x \right ) &= \left (-x^{2} \left (\ln \left (x \right )-c_{1} \right )\right )^{\frac {1}{7}} \\ y \left (x \right ) &= -\left (\left (c_{1} -\ln \left (x \right )\right ) x^{2}\right )^{\frac {1}{7}} \left (-1\right )^{\frac {1}{7}} \\ y \left (x \right ) &= \left (\left (c_{1} -\ln \left (x \right )\right ) x^{2}\right )^{\frac {1}{7}} \left (-1\right )^{\frac {6}{7}} \\ y \left (x \right ) &= -\left (\left (c_{1} -\ln \left (x \right )\right ) x^{2}\right )^{\frac {1}{7}} \left (-1\right )^{\frac {5}{7}} \\ y \left (x \right ) &= \left (\left (c_{1} -\ln \left (x \right )\right ) x^{2}\right )^{\frac {1}{7}} \left (-1\right )^{\frac {2}{7}} \\ y \left (x \right ) &= -\left (\left (c_{1} -\ln \left (x \right )\right ) x^{2}\right )^{\frac {1}{7}} \left (-1\right )^{\frac {3}{7}} \\ y \left (x \right ) &= \left (\left (c_{1} -\ln \left (x \right )\right ) x^{2}\right )^{\frac {1}{7}} \left (-1\right )^{\frac {4}{7}} \\ \end{align*}

Solution by Mathematica

Time used: 0.238 (sec). Leaf size: 181

DSolve[7*x*y'[x]-2*y[x]==-x^2/y[x]^6,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to x^{2/7} \sqrt [7]{-\log (x)+c_1} \\ y(x)\to -\sqrt [7]{-1} x^{2/7} \sqrt [7]{-\log (x)+c_1} \\ y(x)\to (-1)^{2/7} x^{2/7} \sqrt [7]{-\log (x)+c_1} \\ y(x)\to -(-1)^{3/7} x^{2/7} \sqrt [7]{-\log (x)+c_1} \\ y(x)\to (-1)^{4/7} x^{2/7} \sqrt [7]{-\log (x)+c_1} \\ y(x)\to -(-1)^{5/7} x^{2/7} \sqrt [7]{-\log (x)+c_1} \\ y(x)\to (-1)^{6/7} x^{2/7} \sqrt [7]{-\log (x)+c_1} \\ \end{align*}