Find the limit, if it exists of the function:
(7/x - 7/|x|), as this function approaches 0 from the left side.

Question

Find the limit, if it exists of the function: 
(7/x - 7/|x|), as this function approaches 0 from the left side.

anonymous · Answer

For this question, the answer I keep getting is DNE, because I end up with 14/x...

jamesj · Answer

From the left, x < 0.  Hence |x| = .... what?

anonymous · Answer

From the left, then x will be -x.

anonymous · Answer

So if I do that, I get 7/x + 7/x

jamesj · Answer

Hence 7/x - 7/|x| = ....

anonymous · Answer

Which is 14/x, and if you try to even take the limit of that, you get DNE.

anonymous · Answer

Well it always will exist since its only coming from one side?

jamesj · Answer

Right.  Is your web interface telling you that's wrong?

anonymous · Answer

I put DNE into the answer on my electronic assignment, and it says this is "Wrong".

jamesj · Answer

Put in zero and see if that's right, assuming either the question was wrong ("from the right") or your teacher was super-careless.

anonymous · Answer

Even 0 is wrong.

jamesj · Answer

maddening.  "doesn't exist"  is the solution to the problem as given.