$\"\"$

The function is $\"\"$

Substitute $\"\"$ in the function.

$\"\"$

Now we prove the limit $\"\"$ using $\"\"$ definition.

To show that for each $\"\"$ , there exists a $\"\"$ such that $\"\"$ whenever $\"\"$ .

Consider $\"\"$

$\"\"$

Consider $\"\"$

$\"\"$

Observe the relationship between two absolute values $\"\"$ and $\"\"$ .

$\"\"$ .

$\"\"$

The solution of $\"\"$ is $\"\"$ .