> How to find the variations in f?

How to find the variations in f?

Posted at: 2014-06-09 
I have y=(2x+4)/(x+1) i have been asked to make a table of variation for this function. I know that D=R\{-1}. But how do i find the places where the function changes direction? I want to find the value of x and what it gives us. Could someone please give me the answer with detailled intermediary steps?? PS. I need the way to calculate the exact values, not approximations. I could do the approximations. I just don't know how to get the exact values. Thanks in advance.