kill(all)$

van=facebook.com/LearningCalculus$

f(x):=(1/x-x)*abs(x+1/x);

a:[-1+delta,0-delta]$
b:[ 0+delta,1-delta]$

ALeft:[first(a),first(f(a))];
ARite:[second(a),second(f(a))];

BLeft:[first(b),first(f(b))];
BRite:[second(b),second(f(b))];