Chapter 2.6, Problem 20P

Integrating Factor. In each of Problem $19$ through $22$:

Show that the given equation is not exact but becomesexact when multiplied by the given integrating factor.

Solve the equation.

Use a computer to draw several integral curves.

$\left(\frac{\sin y}{y}-2e^{-x}\sin x\right)+\left(\frac{\cos y+2e^{-x}\cos x}{y}\right)y\text{'}=0,\mu (x,y)=y{e}^x$.