Find the integrating factor for the ODE y′+1xy=3y' + \frac{1}{x}y = 3y′+x1y=3.
μ(x)=x\mu(x) = xμ(x)=x
μ(x)=ln(x)\mu(x) = \ln(x)μ(x)=ln(x)
μ(x)=1x\mu(x) = \frac{1}{x}μ(x)=x1
μ(x)=ex\mu(x) = e^xμ(x)=ex