Evaluate $\lim_{x \to 0^-} \left( \frac{1}{x} - \frac{1}{|x|} \right)$ (possible textbook mistake - James Stewart 7th) I was working on a few problems from James Stewart's Calculus book (seventh edition) and I found the following:

Find 
$$\lim_{x \to 0^-} \left( \frac{1}{x} - \frac{1}{|x|} \right)$$

Since there's a $|x|$ on the limit and knowing that $|x| = -x$ for any value less than zero, we have
$$\lim_{x \to 0^-} \left( \frac{1}{x} - \frac{1}{|x|} \right) = \lim_{x \to 0^-} \frac{2}{x}$$
So far so good. Continuing,
$$\lim_{x \to 0^-} \left( \frac{1}{x} - \frac{1}{|x|} \right) = \lim_{x \to 0^-} \frac{2}{x} = - \infty$$
since the denominator becomes smaller and smaller. When checking the textbook's answer I've found the following:


Am I missing something or should the limit really be $- \infty$ ?

bru, I think that the problem is just about terminology. Your derivation is correct, but it is likely that what Stewart is claiming is (I guess) that a limit that goes to $-\infty$ or to $+\infty$ on only one side (as in this example, where the limit is only from the left), is "non existing". Otherwise, the statement "the limit does not exist becuase the denomiator approaches $0$ while the numerator does not" would be simply nonsense.  
