In order for that to equal to an integer,
what's under the radical must be a perfect square. 

We compare the fraction  to the fraction

, and observe that  has a smaller 
numerator and a larger denominator than  which is 3. So  is a perfect
square less than 3. 

The only perfect square less than 3 is 1, so what's under the 
radical must equal to 1.  So

 = 1

Multiply both sides by n+1

3n - 5 = n + 1
    2n = 6
     n = 3

So n=3 and therefore

 =  =  =  = 1

Edwin