3.43 problem 4.8 (b)

Internal problem ID [13021]

Book: Ordinary Differential Equations. An introduction to the fundamentals. Kenneth B. Howell. second edition. CRC Press. FL, USA. 2020
Section: Chapter 4. SEPARABLE FIRST ORDER EQUATIONS. Additional exercises. page 90
Problem number: 4.8 (b).
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_separable]

\[ \boxed {y y^{\prime }=\sin \left (x \right )} \] With initial conditions \begin {align*} [y \left (0\right ) = -4] \end {align*}

Solution by Maple

Time used: 0.14 (sec). Leaf size: 14

dsolve([y(x)*diff(y(x),x)=sin(x),y(0) = -4],y(x), singsol=all)
 

\[ y = -\sqrt {-2 \cos \left (x \right )+18} \]

Solution by Mathematica

Time used: 0.11 (sec). Leaf size: 22

DSolve[{y[x]*y'[x]==Sin[x],{y[0]==-4}},y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to -\sqrt {2} \sqrt {9-\cos (x)} \]