A curve $y=f\left(x\right)$ satisfies the differential equation $(1+x^2)\frac{dy}{dx}+2yx=4x^2$ and passes through the origin then 

The function $y=f\left(x\right)$ is increasing, $\forall x\in R$

The function $f\left(x\right)$ has no inflection point 

The function $y=f\left(x\right)$ has a minima but no maxima

The area enclosed by $y=f^{-1}\left(x\right),$ the x-axis and the ordinate at $x = 2/3$ is $\frac{2}{3}\ln 2$