Find all possible functions with the given derivative.

1.	If $\displaystyle y' = \frac{-1}{x^{2}}$, then $y$	=
2.	If $\displaystyle y' = 1-\frac{1}{x^{2}}$, then $y$	=
3.	If $\displaystyle y' = 3+\frac{1}{x^{2}}$, then $y$	=