Consider the equation (3xy+y2)dx+(x2+xy)dy=0(3xy+y^2)dx + (x^2+xy)dy = 0(3xy+y2)dx+(x2+xy)dy=0. Find the integrating factor μ(x)\mu(x)μ(x) if it exists.
μ=x\mu = xμ=x
μ=x2\mu = x^2μ=x2
μ=1/x\mu = 1/xμ=1/x
μ=x+y\mu = x+yμ=x+y