First graph the two functions to see which one is the top and bottom function and also the point of intersection. In this, the point of intersections are 1 and 1, by solving for x and in this region, the first function is above the second function.
So solve a definite integral between -1 and 1 for 1/ (4x^2 +1) minus 1/(x^2 +4). Or since they are both even functions, you can also multiply the definite integral between 0 and 1 for 1/ (4x^2 +1) minus 1/(x^2 +4) by 2.
Ceebs doing it myself but the link is the integral working out.