$y=(1+x) /(1-x)$ হলে, $\frac{d y}{d x}$ এর মান -

$\frac{-2}{(1-x)^{2}}$

$\frac{3}{(1-x)^{2}}$

$\frac{2}{(1-x)^{2}}$

$\frac{2}{(1+x)^{2}}$