What does it mean to say a point is fixed by f to the m?
Conditions
- is a function.
- is a positive integer.
- is a point in the domain of .
Reasoning, step by step
- Take the definition of a periodic point of period : .
- Regard the -fold iterate itself as a new function .
- Then the equation becomes , which matches the fixed-point form.
- Conclude that a point of period for can be viewed as a fixed point of the iterate .
Example
The same idea is restated in a useful form: saying has period is the same as saying is fixed by the iterate . This links the new definition back to the original fixed-point equation by replacing with .
Common misconceptions
- Thinking that means multiplying the function by .
- Assuming that a point fixed by must also be fixed by .
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Answers are generated from source material and independently checked. Consult the original video or creator if something is unclear.