Proving that Use the following definition for the nonexistence of a limit. Assume f is de...

Proving that Use the following definition for the nonexistence of a limit. Assume f is defined for all values of x near a, except possibly at a. We write  if for some ε > 0, there is no value of δ > 0 satisfying the condition

Let

Prove that  does not exist for any value of a. (Hint: Assume  for some values of a and L and let .)