Determine the integrating factor for the linear equation y′+2y=4y' + 2y = 4y′+2y=4.
μ(x)=2\mu(x) = 2μ(x)=2
μ(x)=e2\mu(x) = e^{2}μ(x)=e2
μ(x)=e2x\mu(x) = e^{2x}μ(x)=e2x
μ(x)=2x\mu(x) = 2xμ(x)=2x