1.80 problem 80

Internal problem ID [7661]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 1, linear first order
Problem number: 80.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [y=_G(x,y')]

Solve \begin {gather*} \boxed {y^{\prime }+f \relax (x ) \sin \relax (y)+\left (1-f^{\prime }\relax (x )\right ) \cos \relax (y)-f^{\prime }\relax (x )-1=0} \end {gather*}

Solution by Maple

Time used: 0.102 (sec). Leaf size: 41

dsolve(diff(y(x),x) + f(x)*sin(y(x)) + (1-diff(f(x),x))*cos(y(x)) - diff(f(x),x) - 1=0,y(x), singsol=all)
 

\[ y \relax (x ) = 2 \arctan \left (\frac {-{\mathrm e}^{\int f \relax (x )d x}+\left (\int {\mathrm e}^{\int f \relax (x )d x}d x \right ) f \relax (x )+c_{1} f \relax (x )}{c_{1}+\int {\mathrm e}^{\int f \relax (x )d x}d x}\right ) \]

Solution by Mathematica

Time used: 0.048 (sec). Leaf size: 59

DSolve[y'[x] + f[x]*Sin[y[x]] + (1-f'[x])*Cos[y[x]] - f'[x]- 1==0,y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to 2 \operatorname {ArcTan}\left (f(x)+\frac {\exp \left (-\int _1^x-f(K[1])dK[1]\right )}{\int _1^x-\exp \left (-\int _1^{K[2]}-f(K[1])dK[1]\right )dK[2]+c_1}\right ) \\ \end{align*}