5.11 problem 7

Internal problem ID [985]

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: 7.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_Bernoulli]

\[ \boxed {y^{\prime }-2 y-x y^{3}=0} \] With initial conditions \begin {align*} \left [y \left (0\right ) = 2 \sqrt {2}\right ] \end {align*}

Solution by Maple

Time used: 0.031 (sec). Leaf size: 13

dsolve([diff(y(x),x)-2*y(x)=x*y(x)^3,y(0) = 2*2^(1/2)],y(x), singsol=all)
 

\[ y \left (x \right ) = \frac {4}{\sqrt {-8 x +2}} \]

Solution by Mathematica

Time used: 1.869 (sec). Leaf size: 34

DSolve[{y'[x]-2*y[x]==x*y[x]^3,y[0]==2*Sqrt[2]},y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to \frac {2 i \sqrt {2} e^{2 x}}{\sqrt {e^{4 x} (4 x-1)}} \]