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    (Original post by mynameisntbobk)
    256 * -0.75^n is not -196^n

    what I'd suggest is on your second line, divide both sides by 256
    Isn't it -192^n? i typed -192^n.
    When dividing by 256 and simplifying and stuff I get n=13.047 this probably sounds stupid but why is the final answer 14?
    Also, what was wrong with my method?
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    (Original post by jadecross)
    Isn't it -192^n? i typed -192^n.
    When dividing by 256 and simplifying and stuff I get n=13.047 this probably sounds stupid but why is the final answer 14?
    Also, what was wrong with my method?
    Ah right, sorry, but even still, that's not right, think about laws of indices. the exponential 'n' is only raised to -0.75, so if you did multiply them together, you'd still get 256*-0.75^n

    Yep, that answer sounds about right. It's 14, because the question asks you for the smallest value of n, to which it exceeds 1000. technically, the smallest answer would be your 13.04... but you tend to round it to the nearest integer. It can't be 13 as that won't exceed 1000, as 13.04.. does, so it has to be 14.

    Like I explained above, you just need to be careful when multiplying a number with a power that's raised to a number.

    a * b = c

    a * b^n =/= c (unless n=1)

    Look at it practically, imagine n = 3, a = 5 and b = 2

    5 * 2 = 10
    5 * 2^3 = 40

    what you did was:

    5 * 2^3 = 10^3, which as you can see isn't right. Remember if a power is raised to a specific number, then it's only raised to that number
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    (Original post by mynameisntbobk)
    Ah right, sorry, but even still, that's not right, think about laws of indices. the exponential 'n' is only raised to -0.75, so if you did multiply them together, you'd still get 256*-0.75^n

    Yep, that answer sounds about right. It's 14, because the question asks you for the smallest value of n, to which it exceeds 1000. technically, the smallest answer would be your 13.04... but you tend to round it to the nearest integer. It can't be 13 as that won't exceed 1000, as 13.04.. does, so it has to be 14.

    Like I explained above, you just need to be careful when multiplying a number with a power that's raised to a number.

    a * b = c

    a * b^n =/= c (unless n=1)

    Look at it practically, imagine n = 3, a = 5 and b = 2

    5 * 2 = 6
    5 * 2^3 = 40

    what you did was:

    5 * 2^3 = 10^3, which as you can see isn't right. Remember if a power is raised to a specific number, then it's only raised to that number
    Thank you so much, this makes sense now
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    (Original post by jadecross)
    Thank you so much, this makes sense now
    No problem, glad I helped
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    How do you work out percentage change for integration ???
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    (Original post by Xx4L3x)
    How do you work out percentage change for integration ???
    I believe it is this \dfrac{B-A}{A} \times 100 and then put it as a percent, where B is the new value and A is the old value, this what I use for the inflation rate so it should work the same :cool:
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    LOGS QUESTION:::

    Solve 4^(x) − 3(2^(x + 1)) = 0

    QUESTION 5B SOLOMAN C CORE 2

    http://www.tomred.org/uploads/7/7/8/..._solomon_c.pdf

    My workings:

    log4^x = log6^x+1

    Have I gone wrong?
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    Anyone knows if there is something like Somolon papers for OCR S1/D1/FP1?
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    (Original post by Xx4L3x)
    LOGS QUESTION:::

    Solve 4^(x) − 3(2^(x + 1)) = 0

    QUESTION 5B SOLOMAN C CORE 2

    http://www.tomred.org/uploads/7/7/8/..._solomon_c.pdf

    My workings:

    log4^x = log6^x+1

    Have I gone wrong?
    Hint: 4^x=(2^x)^2.
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    (Original post by Robbie242)
    I belive it is this \dfrac{B-A}{A} \times 100 and then put it as a percent, where B is the new value and A is the old value, this what I use for the inflation rate so it should work the same :cool:
    I retook Unit 2 Economics last Friday as I wasn't happy with my Jan result (even though I got an A overall as AS), plus I wanted as much AS UMS as possible to guarantee at least an A overall for Economics.

    Anyway, there was one question that gave 6 whole marks (80 raw marks total for the paper) just to calculate a new price index! I was like :zomg: :awesome:
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    (Original post by justinawe)
    I retook Unit 2 Economics last Friday as I wasn't happy with my Jan result (even though I got an A overall as AS), plus I wanted as much AS UMS as possible to guarantee at least an A overall for Economics.

    Anyway, there was one question that gave 6 whole marks (80 raw marks total for the paper) just to calculate a new price index! I was like :zomg: :awesome:
    Ah nice, think you did well ? Generally the OCR paper was a pile of piss so I can only expect high grade boundaries again, the essay question was a bit different from normal though, and those who neglected imports/exports failed it immediately. It was ''Discuss whether a high exchange rate will always reduce inflation'' Managed to make about 10 evaluation points haha. Lost 2 marks for calculations though, said average income per month was $45 because I can't type billions and millions into my calculator because I'm stupid

    I decided not to retake unit 1, got 84 and I think I really smashed this one so hopefully 90 overall.

    One question seriously for 6 marks with a calculation that takes like 20seconds? You must've being chuffed .
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    (Original post by Robbie242)
    Ah nice, think you did well ? Generally the OCR paper was a pile of piss so I can only expect high grade boundaries again, the essay question was a bit different from normal though, and those who neglected imports/exports failed it immediately. It was ''Discuss whether a high exchange rate will always reduce inflation'' Managed to make about 10 evaluation points haha. Lost 2 marks for calculations though, said average income per month was $45 because I can't type billions and millions into my calculator because I'm stupid

    I decided not to retake unit 1, got 84 and I think I really smashed this one so hopefully 90 overall.

    One question seriously for 6 marks with a calculation that takes like 20seconds? You must've being chuffed .
    I sure was, plus 6 marks for calculation questions is way more than Edexcel normally gives... usually it's max 2 or 4 marks, if there's any calculation questions at all! :sigh:

    I'm sure I did better than I did in Jan, I somehow missed out an entire 12 marker in Jan so it shouldn't be too hard to beat that :lol:

    I didn't really revise much for it though, I just relied on the fact that unit 4 was similar-ish to unit 2 so I wouldn't be too rusty, and just did a day-before job. So I'm doubting I'll get 90+ UMS (possibly but definitely not confident I will).

    I'm not too concerned about it anyway, smash unit 4 and I'll definitely be looking at an A* overall.
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    I think one of the recent edexcel papers has had a mistake ....anyone can do this mechanics sum please!

    A ball is suspended from the roof of a moving car by a string, which is 7° to the vertical. Find the acceleration of the car.
    Thy gave nothing about the mass etc.

    How to do this? :confused:

    Posted from TSR Mobile
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    (Original post by StUdEnTIGCSE)
    I think one of the recent edexcel papers has had a mistake ....anyone can do this mechanics sum please!

    A ball is suspended from the roof of a moving car by a string, which is 7° to the vertical. Find the acceleration of the car.
    Thy gave nothing about the mass etc.

    How to do this? :confused:

    Posted from TSR Mobile
    Is that the whole question? What paper is this from?
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    (Original post by justinawe)
    Is that the whole question? What paper is this from?
    That was the whole question.
    Is this possible or not. Just say...don't try to do it..
    Then I'll say from what paper.

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    (Original post by StUdEnTIGCSE)
    That was the whole question.
    Is this possible or not. Just say...don't try to do it..
    Then I'll say from what paper.

    Posted from TSR Mobile
    If that's all the information, I don't think it's possible. I mean, only an angle was given...

    However, I kind of doubt that was all the information given, so I'd like to see the paper for myself!
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    (Original post by justinawe)
    If that's all the information, I don't think it's possible. I mean, only an angle was given...

    However, I kind of doubt that was all the information given, so I'd like to see the paper for myself!
    K thanks. So a student like you can't even do it.
    I looked over every inch for any more data but there wasn't any.


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    (Original post by StUdEnTIGCSE)
    K thanks. So a student like you can't even do it.
    I looked over every inch for any more data but there wasn't any.


    Posted from TSR Mobile
    So what's the paper!
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    (Original post by justinawe)
    So what's the paper!
    Its good to get banned once in a while

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    (Original post by StUdEnTIGCSE)
    K thanks. So a student like you can't even do it.
    I looked over every inch for any more data but there wasn't any.


    Posted from TSR Mobile
    Also, if this truly is all the data given, I'd say a=0, because if the ball stays in the same position, that means there's no net resultant force on the ball... just a guess, though.
 
 
 
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