Example 5.3.3
Take

for

.
Look for a limit of

at 0:

is the product of a bounded function (as the sine function is bounded over

, we have

) and a function whose limit at 0 is equal to 0.
Therefore, by Theorem thm sandwich, we have
This means that

has a removable discontinuity at 0.
Figure 3:
A removable discontinuity.
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