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  1. #1
    Senior Member Chelsea's Avatar
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    lim x->infinity (2x^4-3x^2+2x-1)/(x^3-2x^2+2)?

    what is the limit, if it exists

  2. #2
    Junior Member mkm's Avatar
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    This limit= infinity
    take x^4 as a common factor from nominator and denominator, then cancel them. After that substitute directly to get infinity.

  3. #3
    Junior Member ogicu8abruok's Avatar
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    that limit would equal infinity. you can tell because the numerator has a higher power of x than the denominator.

    if you want to see it better, divide the top and bottom by x^4 and you get the fraction going to 2/0

  4. #4
    Junior Member cidyah's Avatar
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    The exponent of the numerator exceeds that of the denominator, so as x goes to infinity, the expression goes to infinity.
    You can prove it by using L'Hopital's Rule should you wish.
    lim x-> inf (2x^4-3x^2+2x-1) / (x^3-2x^2+2)
    lim x->inf (8x^3 -6x^2+2) / (3x^2-4x)
    lim x-> inf (24x^2-12x) / (6x-4)

    lim x-> inf (48x-12) / 6
    = infinity

  5. #5
    Junior Member MartinF's Avatar
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    divide top and bottom by x^3 ?

    limit does not exist ?


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