(1)$ \int \dfrac { \sin \sqrt {x}}{ \sqrt {x}}dx= \underline { \quad \quad \quad }$.
(2) $\int \frac {dx}{ \sqrt {x}(1+x)}=\underline { \quad \quad \quad }$.
(3) $\int \frac {dx}{ \sqrt {x-x^{2}}}=\underline { \quad \quad \quad }$.
(4) $\int \frac {dx}{ \sqrt {x}(2+ \sqrt {x})}=\underline { \quad \quad \quad }$.