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Math Help - exponential function, I can't solve this problem.

  1. #1
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    exponential function, I can't solve this problem.

    I've been struggling with this and I even asked 2 friends of mine to help me but they couldn't solve it.

    Unfortunately, I can't find the function :Z. I hope somebody can help me. thx 4 u time.
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  2. #2
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    An exponential function means this:

    a^x


    If you notice, from 1->2 and 2->3 the value doubles. That's not always a valid hint, but it works for this problem.

    So use 2 as the base and see if you can figure out the exponent.
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  3. #3
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    And try using G(n) = \sum_{i=1}^{n} 2^i.
    Quote Originally Posted by melvis View Post
    I've been struggling with this and I even asked 2 friends of mine to help me but they couldn't solve it.

    Unfortunately, I can't find the function :Z. I hope somebody can help me. thx 4 u time.
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  4. #4
    Behold, the power of SARDINES!
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    Quote Originally Posted by melvis View Post
    I've been struggling with this and I even asked 2 friends of mine to help me but they couldn't solve it.

    Unfortunately, I can't find the function :Z. I hope somebody can help me. thx 4 u time.

    The pattern that you are looking for is this

    \{2,4,8,16,.... \}=\{2^1,2^2,2^3,...,2^{64} \}.

    So write this as a sum you get \sum_{n=1}^{64}2^n

    \sum_{n=0}^{64}2^n=1+\sum_{n=1}^{64}2^n=\frac{1-2^{64+1}}{1-2}=2^{65}-1

    so we get

    1+\sum_{n=1}^{64}2^n=2^{65}-1 \iff \sum_{n=1}^{64}2^n=2^{65}-2=36893488147419103230

    This is alot of rice
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  5. #5
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    thx for the help.
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