Why do early terms not decide the limit of a sequence?
Conditions
- The sequence has a candidate limit .
- The cutoff is chosen based on .
- The definition applies to all .
Reasoning, step by step
- Identify the cutoff for a given tolerance .
- Observe that the definition only requires for .
- Note that terms with may lie outside the tolerance band.
- Conclude that finitely many early exceptions do not affect the limit.
- Recognize that is an effective threshold, not necessarily the smallest or unique one.
Example
The card 'Early terms do not decide the limit' states: 'Finitely many exceptions before the cutoff do not affect convergence. A cutoff is an effective threshold, not necessarily the smallest or unique one.'
Common misconceptions
- Believing that all terms must satisfy the error bound.
- Thinking that the cutoff must be the smallest possible integer.
- Assuming that early terms outside the band invalidate the limit.
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