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    (Original post by reubenkinara)
    I'm probably not the guy to ask this time Didn't even the get the first one. I understood how from the hint, but not how he got from the series to the hint.
    You've done 1-r on the denominator, when 10^1/4=1.77... which is different from the common ratio

    LATEX STOP BEING A ****ING ASS

    10^1/4 / 10^1/2 = r
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    (Original post by reubenkinara)
    I'm probably not the guy to ask this time Didn't even the get the first one. I understood how from the hint, but not how he got from the series to the hint.
    Awwh, hmm I was thinking... The whole thing keeps getting square rooted right? can we do a series just for the powers? as they double? so the ratio is 2.. and after we find the sum to infinity to that can we use that ans on 10...
    This is probably rubbish
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    (Original post by MathsNerd1)
    If this is from C2 then I've clearly forgotten the content.
    (Original post by reubenkinara)
    Oh. Not from C2, just when I was doing some extra maths with some mates awhile ago. I came across the first example and understood the concept. Now. I'm just painfully lost.
    (Original post by tigerz)
    Do we get the ratio by doing  \frac{10^\frac{1}{4}}{10^\frac{1  }{2}}?
    Try setting it equal to x and dividing both sides by \sqrt{10}

    (Original post by Lord of the Flies)
    Pf, at least make the result pretty Felix:

    \sqrt{\dfrac{1}{\phi^2}+ \sqrt{\dfrac{1}{\phi^4}+ \sqrt{\dfrac{1}{\phi^8}+\cdots}}  }

    ... or something
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    (Original post by Felix Felicis)
    Try setting it equal to x and dividing both sides by \sqrt{10}


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    Can you answer it?
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    (Original post by Robbie242)
    You've done 1-r on the denominator, when 10^1/4=1.77... which is different from the common ratio

    LATEX STOP BEING A ****ING ASS

    10^1/4 / 10^1/2 = r
    kk
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    (Original post by MAyman12)
    Can you answer it?
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    x = \sqrt{10 + \sqrt{10^{2} + \sqrt{10^{4} + \sqrt{10^8 + ...}}}}

    \Rightarrow \dfrac{x}{\sqrt{10}} = \displaystyle\underbrace{\sqrt{1 + \sqrt{1 + \sqrt{1 + ...}}}}_{\phi}

    \Rightarrow x = \sqrt{10} \cdot \phi
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    (Original post by Felix Felicis)
    Try setting it equal to x and dividing both sides by \sqrt{10}


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    Still stuck sorry. I'll just get someone to explain it to me?
    Thanks for the hints
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    (Original post by Felix Felicis)
    Try setting it equal to x and dividing both sides by \sqrt{10}


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    Set what equal to x, then I'm good to go tbh
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    (Original post by Robbie242)
    Set what equal to x, then I'm good to go tbh
    The series.
    This: \sqrt{10 + \sqrt{10^{2} + \sqrt{10^{4} + ... }}}
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    (Original post by Robbie242)
    Set what equal to x, then I'm good to go tbh
    \sqrt{10 + \sqrt{10^{2} + \sqrt{10^{4} + ... }}}
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    (Original post by Felix Felicis)
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    x = \sqrt{10 + \sqrt{10^{2} + \sqrt{10^{4} + \sqrt{10^8 + ...}}}}

    \Rightarrow \dfrac{x}{\sqrt{10}} = \displaystyle\underbrace{\sqrt{1 + \sqrt{1 + \sqrt{1 + ...}}}}_{\phi}

    \Rightarrow x = \sqrt{10} \cdot \phi
    -.- Your questions are the most difficult 'easy' questions :zomg:
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    (Original post by tigerz)
    -.- Your questions are the most difficult 'easy' questions :zomg:
    Damn straight!
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    (Original post by MathsNerd1)
    Damn straight!
    Totally neglecting my chemistry revision >.< someone was clearly upset with me thinking about giving up the earlier question lols
    They literally require you think with pure logic
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    (Original post by tigerz)
    Totally neglecting my chemistry revision >.< someone was clearly upset with me thinking about giving up the earlier question lols
    They literally require you think with pure logic
    I'm exactly the same and yeah, someone didn't like the fact I pointed you out to the hint They do and that is why I get annoyed that I can't see the answer straight away :mad:
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    (Original post by Felix Felicis)
    \sqrt{10 + \sqrt{10^{2} + \sqrt{10^{4} + ... }}}
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    Sinfinity=x

    so we know that r<|1| therefore the series tends towards infinity and the sum to infinity exists

    x=\sqrt{10+ \sqrt{10^{2}+\sqrt{10^4{}+ ...}}}
    Dividing by root 10
    \dfrac{x}{\sqrt{10}}=\sqrt{1+ \sqrt{1^{2}+\sqrt{1^4{}+....}}} therefore multiplying by root 10
    x=\sqrt{10}


    hmm I like but I'm not sure about the powers, in my second line I swear the squared powers won't matter as the series will just constantly be 1,1,1,1,1,1,1,,1,1,1,1,,1,1,1,1, ,1,1,1,1
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    (Original post by MathsNerd1)
    I'm exactly the same and yeah, someone didn't like the fact I pointed you out to the hint They do and that is why I get annoyed that I can't see the answer straight away :mad:
    Haha, :O oh yeah! All you were doing was helping me out, infact was the only reason I could solve the first one!
    I find myself over complicating the questions and doing all sorts! Yeah I get annoyed at myself for not seeing what to do :facepalm:
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    (Original post by Robbie242)
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    Sinfinity=x

    so we know that r<|1| therefore the series tends towards infinity and the sum to infinity exists

    x=\sqrt{10+ \sqrt{10^{2}+\sqrt{10^4{}+ ...}}}
    Dividing by root 10
    \dfrac{x}{\sqrt{10}}=\sqrt{1+ \sqrt{1^{2}+\sqrt{1^4{}+....}}} therefore multiplying by root 10
    x=\sqrt{10}


    hmm I like but I'm not sure about the powers, in my second line I swear the squared powers won't matter as the series will just constantly be 1,1,1,1,1,1,1,,1,1,1,1,,1,1,1,1, ,1,1,1,1
    You're almost there, but:

    \sqrt{1 + \sqrt{1 + \sqrt{1 + ...}}} \neq 1 If you haven't seen the result before, you may need to evaluate this separately as well
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    (Original post by Robbie242)
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    Sinfinity=x

    so we know that r<|1| therefore the series tends towards infinity and the sum to infinity exists

    x=\sqrt{10+ \sqrt{10^{2}+\sqrt{10^4{}+ ...}}}
    Dividing by root 10
    \dfrac{x}{\sqrt{10}}=\sqrt{1+ \sqrt{1^{2}+\sqrt{1^4{}+....}}} therefore multiplying by root 10
    x=\sqrt{10}


    hmm I like but I'm not sure about the powers, in my second line I swear the squared powers won't matter as the series will just constantly be 1,1,1,1,1,1,1,,1,1,1,1,,1,1,1,1, ,1,1,1,1
    I swear it simplifies as you go along?

    Felix your maths questions are just one of a kind lols
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    (Original post by Felix Felicis)
    You're almost there, but:

    \sqrt{1 + \sqrt{1 + \sqrt{1 + ...}}} \neq 1 If you haven't seen the result before, you may need to evaluate this separately as well
    Hmm pondering on how to get the result root 10 other than that assumption/test, how would I necessarily be able to evaluate that, if its 1-r on the denominator for sinfinity for x/root 10 then that would equal 0 and thats bad. Hmm I'm not entirely sure, any hints felix?

    And also its the sum to infinity to this suggests 1+1+1+1.... with roots blahblah which certainly can't equal 1 (trying to make sense of this using c2 knowledge derp)
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    (Original post by tigerz)
    Haha, :O oh yeah! All you were doing was helping me out, infact was the only reason I could solve the first one!
    I find myself over complicating the questions and doing all sorts! Yeah I get annoyed at myself for not seeing what to do :facepalm:
    Indeed as I could only imagine how much the question was annoying you and yeah, I tend to do that all the time but now I'm purposely trying to make an easier question harder for some sheer fun
 
 
 
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