The limit of the function is .

definition of limit :

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if for every number of , there exists a such number whenever .

Consider .

Consider .

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Observe the relation between and  .

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must be in terms of , with no other variables depending on it.

Since .

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value is minimum, when is maximum.

From the above, the restrictions are and .

Then the obtained relation is .

Verification :

For every number of if then .

Consider .

Now consider .

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