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    What does this function notation mean?

    f^n(x)
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    Usually (f(x))^n, but it could mean a couple of other things. What is the context?
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    It's the first question on a C2 paper I'm doing, it's to do with the function f(x)=x^3+3x^2+5.

    It just says find f^n(x).
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    Are you sure it doesn't say: find f'(x) instead?
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    (Original post by Kolya)
    Are you sure it doesn't say: find f'(x) instead?
    Yep. Positive.
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    If you are sure, then f^n(x) can also mean the nth derivative of f(x). In other words, write down the different functions obtained for different values of n. There are four cases for you to consider.
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    (Original post by Kolya)
    If you are sure, then f^n(x) can also mean the nth derivative of f(x). In other words, write down the different functions obtained for different values of n. There are four cases for you to consider.
    Ok, this sounds likely Thanks!
    Do positive and negative integers come into these four cases?
    I've never seen a C2 question like this before.
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    I've been studying Chaos, and for us, the notaton f^n(x) is generally used to refer to the map f(f(f...f(x)) where f is applied n times~
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    Ah, wait! There is a black mark on my test paper that makes it look like an n, but I've worked out it's the second derivative, f^''(x). I thought I'd never come across the nth derivative before.
    Thanks anyway
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    (Original post by Kolya)
    If you are sure, then f^n(x) can also mean the nth derivative of f(x). In other words, write down the different functions obtained for different values of n. There are four cases for you to consider.
    There'd be brackets around the n for the nth derivative. :p:
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    (Original post by yusufu)
    There'd be brackets around the n for the nth derivative. :p:
    I know, but I was just trying to come up with a possible interpretation that fitted the context of the question.
 
 
 
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