$$\displaystyle\frac{d}{d x } \left( \sqrt{ x } + \frac{ 2 }{ { x }^{ 2 } } -3 \right)$$
$\frac{1}{2\sqrt{x}}-\frac{4}{x^{3}}$
$-\frac{1}{4x^{\frac{3}{2}}}+\frac{12}{x^{4}}$
