Internal problem ID [2053]
Book: Differential Equations by Alfred L. Nelson, Karl W. Folley, Max Coral. 3rd ed. DC heath.
Boston. 1964
Section: Exercise 12, page 46
Problem number: 22.
ODE order: 1.
ODE degree: 1.
CAS Maple gives this as type [_separable]
\[ \boxed {y^{\prime }-\cos \left (x \right )^{2} \cos \left (y\right )=0} \]
✓ Solution by Maple
Time used: 0.078 (sec). Leaf size: 69
dsolve(diff(y(x),x)=cos(y(x))*cos(x)^2,y(x), singsol=all)
\[ y = \arctan \left (\frac {c_{1}^{2} {\mathrm e}^{x +\frac {\sin \left (2 x \right )}{2}}-1}{c_{1}^{2} {\mathrm e}^{x +\frac {\sin \left (2 x \right )}{2}}+1}, \frac {2 c_{1} {\mathrm e}^{\frac {x}{2}+\frac {\sin \left (2 x \right )}{4}}}{c_{1}^{2} {\mathrm e}^{x +\frac {\sin \left (2 x \right )}{2}}+1}\right ) \]
✓ Solution by Mathematica
Time used: 0.942 (sec). Leaf size: 41
DSolve[y'[x]==Cos[y[x]]*Cos[x]^2,y[x],x,IncludeSingularSolutions -> True]
\begin{align*} y(x)\to 2 \arctan \left (\tanh \left (\frac {1}{8} (2 x+\sin (2 x)+c_1)\right )\right ) y(x)\to -\frac {\pi }{2} y(x)\to \frac {\pi }{2} \end{align*}