What is \(\mathop {\lim }\limits_{{\rm{h}} \to 0} \frac{{\sqrt {2{\rm{x}} + 3{\rm{h}}} - \sqrt {2{\rm{x}}} }}{{2{\rm{h}}}}\) equal to?
1
\(\frac{1}{{2\sqrt {2{\rm{x}}} }}\)
2
\(\frac{3}{{\sqrt {2{\rm{x}}} }}\)
3
\(\frac{3}{{2\sqrt {2{\rm{x}}} }}\)
4
\(\frac{3}{{4\sqrt {2{\rm{x}}} }}\)