Which of the following is an integrating factor for (2y+3x2)dx+xdy=0(2y + 3x^2)dx + x dy = 0(2y+3x2)dx+xdy=0?
μ(x)=x\mu(x) = xμ(x)=x
μ(x)=x2\mu(x) = x^2μ(x)=x2
μ(y)=y\mu(y) = yμ(y)=y
μ(x)=ex\mu(x) = e^xμ(x)=ex