Answer:
Check the attached image for the sake of my sanity typing integrals in these.
Notes on the red marks.
1. From the first to the second passage I multiplied top and bottom by 2. The bottom one stood outside the integral by linearity, the top got inside to get the derivative of the denominator.
2. Quick y substitution, it's a dy/y which should get integrated as the logarythm of the absolute value. This is a situation where you can skip it since you know that you are dealing with positive values (1 is positive, and 1 plus something squared is even greater than 1 which was positive already).
The area as x diverges also diverges