$\frac{d}{d x}\left\{\frac{x^{2}}{x^{2}-4}\right\}$ এর মান কত ?

$\frac{-8 x}{\left(x^{2}-4\right)^{2}}$

$-\frac{6 x}{\left(x^{2}+4\right)^{2}}$

$\frac{4 x}{\left(x^{2}-8\right)^{2}}$

$\frac{4 x}{\left(x^{2}+8\right)^{2}}$