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    Never mind I'm wrong - wish I'd had time to check!!!
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    (Original post by Torticci)
    Can someone explain the limiting factor one and how it was 3/5? I though it was 2.4 cos then the denominator would equal 0 and the fraction would be undefined


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    Limiting factor's really easy.
    Start by dividing everything by the highest power of n (in this case it was just n)
    You'd have got 3/5+(12/n). As n increases, 12/n gets smaller and smaller (closer and closer to 0) so it can be ignored.
    Hence 3/5.
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    (Original post by ErinMei)
    That is just an A* distinction i think depending on grade boundaries. I think i got 55 marks at the least

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    I thought you got like 65 or something xD!

    (Original post by Redcoats)
    Which question was the x = -55 ?
    It was on the question where you had the brackets and then to the power of a third.
    Solve for x

    (Original post by NiamhM1801)
    For the inequality, t asked for integer solutions. Wouldn't you therefore have had to put 9, 10 and 11?
    Other than that and question 6 (which I knew I'd completely messed up) I think I've done very well
    Yeah, I read the question wrong... I'm so struggling these days with just reading questions correctly .

    (Original post by NiamhM1801)
    Oh, also I didn't get +75x for the cubic, I got +25x. I'm probably wrong though haha
    It was (x-5)^3 I think and the answer is +75x so I think you got it wrong .
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    (Original post by NiamhM1801)
    Never mind I'm wrong - wish I'd had time to check!!!
    Don't worry, I thought I was running out of time - so I rushed it - only to realise I had 30 or so minutes to spare.
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    (Original post by Torticci)
    Can someone explain the limiting factor one and how it was 3/5? I though it was 2.4 cos then the denominator would equal 0 and the fraction would be undefined


    Posted from TSR Mobile
    The nth term was 3n / 5n +12

    Factor out n : n(3)/ n(5+12/n)

    Cancel out the n's: 3 / (5 + 12/n)

    Substitute infinity: 3/ (5 + 12 / infinity)

    12 / infinity tends towards 0 so: 3 / 5 + 0

    Therefore the limiting value is 3 / 5
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    (Original post by Chittesh14)
    I thought you got like 65 or something xD!



    It was on the question where you had the brackets and then to the power of a third.
    Solve for x



    Yeah, I read the question wrong... I'm so struggling these days with just reading questions correctly .



    It was (x-5)^3 I think and the answer is +75x so I think you got it wrong .
    Pretty sure it was x = 121 for the power of a third question : (3- sqrt(x))^1/3 = -2 or something
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    (Original post by Chittesh14)
    I thought you got like 65 or something xD!



    It was on the question where you had the brackets and then to the power of a third.
    Solve for x



    Yeah, I read the question wrong... I'm so struggling these days with just reading questions correctly .



    It was (x-5)^3 I think and the answer is +75x so I think you got it wrong .
    (Original post by Chittesh14)
    Don't worry, I thought I was running out of time - so I rushed it - only to realise I had 30 or so minutes to spare.
    Oh don't worry we all are - in biology today in the thing that asked about lifestyle factors I talked about medical history and in the one that asked about medical history I made stuff up as I couldn't remember anything about medical history!!

    And I know, our clock didn't get reset so it finished on 2:46, really hard to judge your timings like that! And at least it wasn't the other way round!
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    (Original post by Redcoats)
    Pretty sure it was x = 45 for the power of a third question : (3- sqrt(x))^1/3 = -2 or something
    I definitely got 55, not sure about the positive or negative though.
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    Thanks for the limiting factor help!


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    (Original post by Redcoats)
    Pretty sure it was x = 121 for the power of a third question : (3- sqrt(x))^1/3 = -2 or something
    No idea man, we can only tell once we know the exact question again .
    All I remember is 9 - 64 = x lol.
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    (Original post by NiamhM1801)
    I definitely got 55, not sure about the positive or negative though.
    Sorry not 45, x = 121. Check for yourself, it works!

    (3 - sqrt(x))1/3 = -2

    3 - sqrt(x) = -8

    - sqrt(x) = -11

    sqrt(x) = 11

    Therefore x = 112

    So x = 121
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    (Original post by Redcoats)
    Sorry not 45, x = 121. Check for yourself, it works!

    (3 - sqrt(x))1/3 = -2

    3 - sqrt(x) = -8

    - sqrt(x) = -11

    sqrt(x) = 11

    Therefore x = 112

    So x = 121
    Mathway says the same haha, what did I do so wrong lmao
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    (Original post by Chittesh14)
    No idea man, we can only tell once we know the exact question again .
    All I remember is 9 - 64 = x lol.
    Are you sure your not mixing up questions, i.e. are you thinking of the cos theta or sqrt(125) + sqrt(20) = sqrt(80) + sqrt(x) where x = 45 question? The exact question, I'm pretty sure, is
    (3 - sqrt(x))1/3 = -2, solve for x.
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    (Original post by NiamhM1801)
    Mathway says the same haha, what did I do so wrong lmao
    Don't worry! What do you think your mark will be out of 70?
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    My method:
    (3-√x)¹/₃ = -2
    3-√x = -8
    9-x= 64
    64-9=-x=55
    x=-55
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    (Original post by Redcoats)
    Don't worry! What do you think your mark will be out of 70?
    I'm not sure as the marks aren't given, however this has certainly boosted my confidence! Definitely think between 55 and 60 which, although my lowest score yet (I owe this to nerves as I did panic near the start), I'm quite proud of.
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    (Original post by NiamhM1801)
    Mathway says the same haha, what did I do so wrong lmao
    We both ****ed up lol.

    (Original post by Redcoats)
    Sorry not 45, x = 121. Check for yourself, it works!

    (3 - sqrt(x))1/3 = -2

    3 - sqrt(x) = -8

    - sqrt(x) = -11

    sqrt(x) = 11

    Therefore x = 112

    So x = 121
    That's weird though, what I did and probably NiamhM too:


    (3 - sqrt(x))1/3 = -2

    (31/3 - x 1/6) = -2
    9 - x = 64
    x = -55

    (Original post by Redcoats)
    Are you sure your not mixing up questions, i.e. are you thinking of the cos theta or sqrt(125) + sqrt(20) = sqrt(80) + sqrt(x) where x = 45 question? The exact question, I'm pretty sure, is
    (3 - sqrt(x))1/3 = -2, solve for x.
    Nah I got 45 for that, and -55 for this - I'm wrong, you're right. I'm dead.
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    (Original post by NiamhM1801)
    My method:
    (3-√x)¹/₃ = -2
    3-√x = -8
    9-x= 64
    64-9=-x=55
    x=-55
    I'm not too sure about your method because:

    First, x cannot equal a negative number as you're square rooting it.

    Secondly, when you squared both sides of the equation in 3 - sqrt(x) = -8, you square rooted incorrectly:

    Square rooting both sides gives: (3-sqrt(x))2 = (-8)2

    This is : (9 - 6sqrt(x) +x) = 64 as it is a double bracket, you can't just square each term as you have done.

    Really sorry to tell you this! I'm sure you've still got your A^ - remember the boundaries for such are really low
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    (Original post by Chittesh14)
    We both ****ed up lol.



    That's weird though, what I did and probably NiamhM too:


    (3 - sqrt(x))1/3 = -2

    (31/3 - x 1/6) = -2
    9 - x = 64
    x = -55



    Nah I got 45 for that, and -55 for this - I'm wrong, you're right. I'm dead.
    Oops haha

    And no I didn't do it that way, as you can see above. But I got the same answer as you.

    Lmao same here. Although I'm looking forward to Friday's now
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    I'm just going down every post lol, I think I've lost A*^ now.
 
 
 
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