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    is the statement if f(x)=3x³+2x²+5x+1 then f(x) is o(x²) correct?
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    No. Why did you think it was?
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    (Original post by DFranklin)
    No. Why did you think it was?
    Because 2<3

    hol up is then o(x^4) correct? cus if you divide by x^4 then the bottom of f(x)/x^4 goes to 0 quicker than f(x)
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    If you're concerned about the behaviour for large X, then yes, any power of x greater than 3 will work.

    If your concern is what happens when x is small, that's a different story.
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    (Original post by DFranklin)
    If you're concerned about the behaviour for large X, then yes, any power of x greater than 3 will work.

    If your concern is what happens when x is small, that's a different story.
    ok so just to clear up both these statements are correct?
    if f(x)=3x³+2x²+5x+1 then f(x) is o(x^4)
    if f(x)=3x³+2x²+5x+1 then f(x) is O(x³)
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    (Original post by will'o'wisp2)
    ok so just to clear up both these statements are correct?
    if f(x)=3x³+2x²+5x+1 then f(x) is o(x^4)
    if f(x)=3x³+2x²+5x+1 then f(x) is O(x³)
    Repeating myself: if you are talking about the behaviour for large x then these are correct.

    Note that it would also correct to say that f(x) is o(x^pi) or o(x^27) or O(x^4) (to throw out a few random examples).
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    (Original post by DFranklin)
    Repeating myself: if you are talking about the behaviour for large x then these are correct.

    Note that it would also correct to say that f(x) is o(x^pi) or o(x^27) or O(x^4) (to throw out a few random examples).
    Got it and cleared up that my statements are right as x\Rightarrow \infity

    So then i can't use O(x^2) for the above examples where the largest power is 3?
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    (Original post by will'o'wisp2)
    Got it and cleared up that my statements are right as x\Rightarrow \infity

    So then i can't use O(x^2) for the above examples where the largest power is 3?
    No.
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    (Original post by DFranklin)
    No.
    Great, thanks.
 
 
 
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