/ 1 \ lim atan|-------| x->-2+ | 2| \-4 + x /
Limit(atan(1/(-4 + x^2)), x, -2)
-pi ---- 2
= -1.5707963267949
/ 1 \ lim atan|-------| x->-2- | 2| \-4 + x /
pi -- 2
= 1.5707963267949
-1.5707963267949