The limit is
.
Definition :
\If
be the function is defined on
then
,
it means that for every
there is a corresponing number
such that if
then
.
From the definition,
\
Here
.

Determine the values of
for which the curve lies between horizontal lines.
Horizontal line:
.
Consider
.
Graph :
\Graph the function
:

Observe the graph.
\when
.
Therefore
.
When
then
.