28: When n grows large, the "+1" and "−1" parts in the ratio can be ignored. Thus the type is

This is an indeterminate power, and the standard procedure can be applied: Use the "e to ln" trick and pass to the limit of the expression inside the exponential.

It is also possible to try to change the ratio into a form leading to an e^c-type limit, see the box "exponential".

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