/ 4 \ | x 2| lim |-1 + -- - x | x->oo\ 2 /
Limit(-1 + x^4/2 - x^2, x, oo, dir='-')
oo
/ 4 \ | x 2| lim |-1 + -- - x | x->1+\ 2 /
-3/2
= -1.5
/ 4 \ | x 2| lim |-1 + -- - x | x->1-\ 2 /
-1.5