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    (Original post by L'Evil Fish)
    Oh. You want me to do the question :lol: right, what is it again?



    If you wouldn't mind

    Given that F(x)=a+bx for 0\leq x \leq 1

    Find the value of the constants a and b, piss easy question but its still there for the lols. A question very similar to this one came up in my S2 exam
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    (Original post by reubenkinara)
    Each to there own I suppose. How's maths revision? I haven't managed to start yet but I'm not too worried. Are you in the zone, i.e averaging \geq{70}?
    For C4? I've done about 4-5 past papers all about 73 marks and my mock being 100% so they gave me the rest of the week off as I had my Chemistry in the way first and they've never had anyone get 100 in a mock before, however the rest of the class were slipping up with a few questions so only got 60/75 max so they've still got some way to go and I just need to keep it up and not get lazy on the day. Also you've got plenty of time so I wouldn't worry too much as I only started my C3 papers yesterday and on the 2 I did I got 72+ so its a good start really
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    (Original post by MathsNerd1)
    For C4? I've done about 4-5 past papers all about 73 marks and my mock being 100% so they gave me the rest of the week off as I had my Chemistry in the way first and they've never had anyone get 100 in a mock before, however the rest of the class were slipping up with a few questions so only got 60/75 max so they've still got some way to go and I just need to keep it up and not get lazy on the day. Also you've got plenty of time so I wouldn't worry too much as I only started my C3 papers yesterday and on the 2 I did I got 72+ so its a good start really
    Yep, that's great? Have you ever been stuck on a C3/C4 Q? It appears that on that specific thread you're constantly giving help!
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    (Original post by Robbie242)
    Given that F(x)=a+bx for 0\leq x \leq 1

    Find the value of the constants a and b, piss easy question but its still there for the lols. A question very similar to this one came up in my S2 exam
    (a + b/2) = 1

    What else can be formed?
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    (Original post by reubenkinara)
    Yep, that's great? Have you ever been stuck on a C3/C4 Q? It appears that on that specific thread you're constantly giving help!
    There has been a few but I just hack away at them until I actually get the answer and it doesn't tend to worry me as I normally have about 40 minutes in the exam where I can spend as long as I want trying to get through the question I'm unable to answer, I also take a second look at the information in the book for that topic to correct where I made the mistake in the first place. It tends to work for me
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    (Original post by L'Evil Fish)
    (a + b/2) = 1

    What else can be formed?

    Madness how did you get that equation?

    It's simply a rectangle for the pdf lol!

    Use the rule that F(1)=1 as its the highest value on the cdf

    Differentiate and then work out the area under the graph, may require a sketch if your not a visual guy, but its a disguised rectangular uniform distribution
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    (Original post by Robbie242)
    Madness how did you get that equation?

    It's simply a rectangle for the pdf lol!

    Use the rule that F(1)=1 as its the highest value on the cdf

    Differentiate and then work out the area under the graph, may require a sketch if your not a visual guy, but its a disguised rectangular uniform distribution
    I don't even know what this is :rofl:

    C.d.f f(1) = 1? Didn't know that!

    I think I should cover those!
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    (Original post by L'Evil Fish)
    Oh. You want me to do the question :lol: right, what is it again?



    If you wouldn't mind
    Of course not, your thread has helped me out a lot! sorry for the bad quality, was a dark day
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    (Original post by L'Evil Fish)
    I don't even know what this is :rofl:

    C.d.f f(1) = 1? Didn't know that!

    I think I should cover those!
    I recommend you get past your current exams before learning new content
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    (Original post by L'Evil Fish)
    I don't even know what this is :rofl:

    C.d.f f(1) = 1? Didn't know that!

    I think I should cover those!
    From S1, from your discerte random variable chapter you should know that for F(X)=P(X\leq x) which therefore, if total probability is 1, and both of these in turn are acting as probability functions, if your probability is less than or equal to the highest limit (i.e. 1) then the total probability of P(X\leq 1) will be 1. does that make sense?
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    (Original post by tigerz)
    Of course not, your thread has helped me out a lot! sorry for the bad quality, was a dark day
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    Thank you ^_^
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    (Original post by L'Evil Fish)
    Thank you ^_^
    Seems a bit too much considering this is probably not on your syllabus, so I've posted the solution in the spoiler if you want to take a look look

    Spoiler:
    Show


    f(x)=\frac{dF(x)}{dx} (a+bx) = b so f(x)=b for 0\leq x\leq1

    Area under graph is simply a rectangle, with width 1 and height b, so 1b=1 -> b=1

    It follows that from the cdf F(1)=1 -> therefore a+b=1 -> a+1=1 -> a=0

    X can also be modeled by a uniform distribution, with X~U[0,1]

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    (Original post by L'Evil Fish)
    Thank you ^_^
    No problemo LOL at how the warning points are: 2,4,10,12 :L

    Please derive a formula for this sequence >.<

    P.S. I swear Edexcel S1 has finished?
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    (Original post by Robbie242)
    From S1, from your discerte random variable chapter you should know that for F(X)=P(X\leq x) which therefore, if total probability is 1, and both of these in turn are acting as probability functions, if your probability is less than or equal to the highest limit (i.e. 1) then the total probability of P(X\leq 1) will be 1. does that make sense?
    Yeah, that does.
    (Original post by Robbie242)
    Seems a bit too much considering this is probably not on your syllabus, so I've posted the solution in the spoiler if you want to take a look look

    Spoiler:
    Show


    f(x)=\frac{dF(x)}{dx} (a+bx) = b so f(x)=b for 0\leq x\ leq1

    Area under graph is simply a rectangle, with width 1 and height b, so 1b=1 -&gt; b=1

    It follows that from the cdf F(1)=1 -> therefore a+b=1 -> a+1=1 -> a=0

    X can also be modeled uniformly, with X~U[0,1]

    Aah, I see that's easy then

    I think I need to take a whole day and cover my S1 properly. It'll take the day I think! So I'll do it tomorrow instead of Chemistry probably :yy:
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    I'm probably the only on on here who's thrown away every single shread of evidence that leads to me having studied AS maths right? Then I remember I start A2 in 3 weeks, so I need to go buy all my notebooks and rulers and whatnot brill, it's not like I don't have enough time to revise for the other exams I have next week
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    There don't seem to be many questions being thrown about tonight. Here's one for you all:

    Spoiler:
    Show


    Let  x be an integer which can be written as the sum of two square numbers. Prove that  2^n x can be written as the sum of two square numbers for all natural numbers n.

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    (Original post by mynameisntbobk)
    I'm probably the only on on here who's thrown away every single shread of evidence that leads to me having studied AS maths right? Then I remember I start A2 in 3 weeks, so I need to go buy all my notebooks and rulers and whatnot brill, it's not like I don't have enough time to revise for the other exams I have next week
    LOOL you joker! I start A2 in2 weeks >.< not planning on buying anything though :P


    (Original post by DJMayes)
    There don't seem to be many questions being thrown about tonight. Here's one for you all:

    Spoiler:
    Show


    Let  x be an integer which can be written as the sum of two square numbers. Prove that  2^n x can be written as the sum of two square numbers for all natural numbers n.

    joostan said you would of liked the fox question earlier :P, I shall attempt this after I finish my chem paper (about 10 mins)
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    (Original post by tigerz)
    LOOL you joker! I start A2 in2 weeks >.< not planning on buying anything though :P




    joostan said you would of liked the fox question earlier :P, I shall attempt this after I finish my chem paper (about 10 mins)
    I probably would (I like most! ) but I've been out all day so haven't seen it.
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    (Original post by DJMayes)
    I probably would (I like most! ) but I've been out all day so haven't seen it.
    It is quite nice It's here
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    (Original post by tigerz)
    LOOL you joker! I start A2 in2 weeks >.< not planning on buying anything though :P
    I have no idea what I was doing ugh, at least I won't make the mistake again.. and yeah, I meant 2 weeks as well, forgot it was half term
 
 
 
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