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    Just thought I'd make a thread to be sure and also because others are probably starting the coursework too. It's not too bad, just tedius, espeically if you've already done numerical methods in further maths. But anyway, a few quick questions just to assure myself if you guys don't mind:

    1)
    Only have to use:
    - Bisection method
    - newton-raphson
    - fixed point iteration with x =g(x).
    Right? nothing else, right?

    2) you have to locate a (or is it all??) root(s?) with each method by randomly chucking in x values to find a sign change and you CANNOT show the root with a graph drawing peice of software untill you've done this??

    3) Bisection falure is with 2 roots close together, that enough?
    4) NR is when starting value on turning point, or close to turning point to find different root, right? Anything else? Or will that be enough?
    5) fixed point iteration can only be with gradient of g(x) at root isn't good enough, right? between -1 and 1, no other way it can fail is there?

    6) compare methods, NR gunna be the best? Use a NEW equation and test for all 3 methods, or one already done? Does it have to have 3+ roorts like NR equation does, or just the one?

    7) anything else I' missing?

    cheers.
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    (Original post by Tallon)
    Just thought I'd make a thread to be sure and also because others are probably starting the coursework too. It's not too bad, just tedius, espeically if you've already done numerical methods in further maths. But anyway, a few quick questions just to assure myself if you guys don't mind:

    1)
    Only have to use:
    - Bisection method
    - newton-raphson
    - fixed point iteration with x =g(x).
    Right? nothing else, right?

    2) you have to locate a (or is it all??) root(s?) with each method by randomly chucking in x values to find a sign change and you CANNOT show the root with a graph drawing peice of software untill you've done this??

    3) Bisection falure is with 2 roots close together, that enough?
    4) NR is when starting value on turning point, or close to turning point to find different root, right? Anything else? Or will that be enough?
    5) fixed point iteration can only be with gradient of g(x) at root isn't good enough, right? between -1 and 1, no other way it can fail is there?

    6) compare methods, NR gunna be the best? Use a NEW equation and test for all 3 methods, or one already done? Does it have to have 3+ roorts like NR equation does, or just the one?

    7) anything else I' missing?

    cheers.
    i'd be willing to be that a lot of members (practically all) have no idea what you're on about with these, we need context. If you want answers, write up the questions.
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    (Original post by Totally Tom)
    i'd be willing to be that a lot of members (practically all) have no idea what you're on about with these, we need context. If you want answers, write up the questions.

    Sorry if I wasn't being clear. It's c3 coursework for MEI. I'm sure everybody does the same coursework across all boards. It's numerical solutations of equations. You pick equations/functions and solve them numerically for the coursework using various methods specified. i thought everybody who does A level maths has to do it?
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    WHAT! how come your starting it now, we've just had our deadline
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    (Original post by clad in armour)
    WHAT! how come your starting it now, we've just had our deadline
    Are you in year 12 just about to go into year 13?
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    I handed this in last friday (yesterday)
    the comparison needs to be done with an equation from one of the other 3 methods and it needs to solve one root for the other two methods
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    1) Yep

    2) All roots for NR, one each for B and FP. "you CANNOT show the root with a graph drawing peice of software untill you've done this??" - haven't been told this bit? not sure :P

    3) Yep

    4) That's enough

    5) Converges when gradient is between |1|, failure is it shooting off somewhere into the atmoshphere when the gradient is steep. But make sure you mention that in your coursework I think you get a specific mark from it (:

    6) Pick one equation you've already done, find one root to 5sf to make sure accuracy is same for all. If you've done FM, NR has second order convergence while FP has first so can mention that to get bonus marks (:

    7) Don't think so. We had marks from talking to our teacher bout it as well, but that's ok if you know what you've done and not copied it or anything

    Hope that helps, sorry if you knew everything anyway didn't wanna be patronising or anything :P
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    (Original post by Tanya.)
    1) Yep

    2) All roots for NR, one each for B and FP. "you CANNOT show the root with a graph drawing peice of software untill you've done this??" - haven't been told this bit? not sure :P

    3) Yep

    4) That's enough

    5) Converges when gradient is between |1|, failure is it shooting off somewhere into the atmoshphere when the gradient is steep. But make sure you mention that in your coursework I think you get a specific mark from it (:

    6) Pick one equation you've already done, find one root to 5sf to make sure accuracy is same for all. If you've done FM, NR has second order convergence while FP has first so can mention that to get bonus marks (:

    7) Don't think so. We had marks from talking to our teacher bout it as well, but that's ok if you know what you've done and not copied it or anything

    Hope that helps, sorry if you knew everything anyway didn't wanna be patronising or anything :P

    Thanks a lot, I appreciate it.
    All I've done for bisection so far for failing is a "V" shaped curve with the tip of the V just touching the x axis twice very close together, and I've made a table of integer x values that are all positive. Is there anything else I can do there? No other way it can fail, is there, really?

    just about to start NR now. I just find 3 roots? or is it all of them? I take it I just randomly pick starting vlaues and see it converge, or maybe pick vlaues of x and use sign change to check for roots or what?
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    (Original post by Tallon)
    Are you in year 12 just about to go into year 13?
    :yes:
    i handed it in yesterday, apparently its incredibly hard to get full marks (18)
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    (Original post by clad in armour)
    :yes:
    i handed it in yesterday, apparently its incredibly hard to get full marks (18)

    I imagine it would be if you have to hand it in before the end of July even when the c3 exam is either january or june next year :\
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    (Original post by Tallon)
    I imagine it would be if you have to hand it in before the end of July even when the c3 exam is either january or june next year :\
    I know, its the centres choice on when to do it though they just have to get the marks in on time
    it doesnt matter that we did it now though we had the same amount of time as everyone else, its because the C2 MEI exam was so disgustingly early
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    (Original post by Tallon)
    All I've done for bisection so far for failing is a "V" shaped curve with the tip of the V just touching the x axis twice very close together, and I've made a table of integer x values that are all positive. Is there anything else I can do there? No other way it can fail, is there, really?
    That sounds fine. Just draw a graph or something as well to show how it fails. Hasn't your teacher given you a tick sheet or something with every mark on it? You just have to show everything on graphs and prove why they do/don't work. And dont use quadratics :P As I did and only realised halfway through I could've just used the quadratic formula (:

    (Original post by Tallon)
    just about to start NR now. I just find 3 roots? or is it all of them? I take it I just randomly pick starting vlaues and see it converge, or maybe pick vlaues of x and use sign change to check for roots or what?
    Sorry I meant all of them, I just did a cubic so had three roots :P. Use the NR formula, pick the whole number intervals the roots are in (use the graph to see) as starting values and see it converge. Then find error bounds (normally 0.00005 if your going to 5sf) by checking for change of sign etc. Then for it failing as you said just do a turning point.
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    Can someone explain to me when Newton-Raphson fails???
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    (Original post by Tallon)
    Sorry if I wasn't being clear. It's c3 coursework for MEI. I'm sure everybody does the same coursework across all boards. It's numerical solutations of equations. You pick equations/functions and solve them numerically for the coursework using various methods specified. i thought everybody who does A level maths has to do it?
    Hint: the people who are most qualified to help you will not be A level maths students.
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    (Original post by jenny28)
    Can someone explain to me when Newton-Raphson fails???
    What's the interative step to get x_{n+1} from x_{n}? Can you see any reason why the process would be undefined?

    hint: think about when you can't divide two numbers.
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    (Original post by around)
    What's the interative step to get x_{n+1} from x_{n}? Can you see any reason why the process would be undefined?

    hint: think about when you can't divide two numbers.
    im thinkin when the bottom is 0? so jus whenever f'(x) is 0??
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    back of the net.
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    (Original post by around)
    back of the net.
    oh right i get it , so when its at like a turning point! thanks for the help!
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    (Original post by DFranklin)
    Hint: the people who are most qualified to help you will not be A level maths students.

    There's no need to be so condescending. It's not as if I need help from an expert. I only wanted some questions answered by people who have done it before. I don't see what the problem is actually because the title is obviously good enough and every single board does the same c3 coursework.
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    we had no coursework at all for either maths or further maths under OCR.
 
 
 
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