If f\left( x \right) = \left\{ {\begin{array}{*{20}{c}} {\dfrac{{\sin \left( {p + 1} \right) + \sin x}}{x}}{,x < 0} \\ \,\,\,\,\,\,\,\,\ {q}\,\,\,\,\,\,\,\,\,\,\,\,\,{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,,x = 0} \\ {\dfrac{{\sqrt {x + {x^2}} - \sqrt x }}{{{x^{{3}/{2}}}}}}{,x > 0} \end{array} } \right.

is continuous at x = 0, then the ordered pair (p, q) is equal to :