7.14 problem 14

Internal problem ID [1074]

Book: Elementary differential equations with boundary value problems. William F. Trench. Brooks/Cole 2001
Section: Chapter 2, First order equations. Exact equations. Integrating factors. Section 2.6 Page 91
Problem number: 14.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [[_1st_order, `_with_symmetry_[F(x)*G(y),0]`]]

\[ \boxed {\cos \left (x \right ) \cos \left (y\right )+\left (\cos \left (y\right ) \sin \left (x \right )-\sin \left (y\right ) \sin \left (x \right )+y\right ) y^{\prime }=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 22

dsolve((cos(x)*cos(y(x)))+(sin(x)*cos(y(x))-sin(x)*sin(y(x))+y(x))*diff(y(x),x)=0,y(x), singsol=all)
 

\[ \cos \left (y \left (x \right )\right ) {\mathrm e}^{y \left (x \right )} \sin \left (x \right )+\left (y \left (x \right )-1\right ) {\mathrm e}^{y \left (x \right )}+c_{1} = 0 \]

Solution by Mathematica

Time used: 0.218 (sec). Leaf size: 28

DSolve[(Cos[x]*Cos[y[x]])+(Sin[x]*Cos[y[x]]-Sin[x]*Sin[y[x]]+y[x])*y'[x]==0,y[x],x,IncludeSingularSolutions -> True]
 

\[ \text {Solve}\left [-2 e^{y(x)} (y(x)-1)-2 e^{y(x)} \sin (x) \cos (y(x))=c_1,y(x)\right ] \]