`lim_{x -> 0} (\sqrt{x + 1} + \sqrt{x + 4} - 3)/(x)`
`= lim_{x -> 0} (\sqrt{x + 1} - 1 + \sqrt{x + 4} - 2)/(x)`
`= lim_{x -> 0} (x + 1 - 1 + x + 4 - 4)/(x(\sqrt{x + 1} + 1)(\sqrt{x + 4} + 2))`
`= lim_{x -> 0} (2)/((\sqrt{x + 1} + 1)(\sqrt{x + 4} + 2))`
`= 2/((0 + 1 + 1).(2 + 2))`
`= 1/4`