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    Can someone help me with this question:

    The point P represents a complex number z in an Argand diagram. Given that  |z+1-i|=1, find the greatest and least values of |z-1|.

    I thought that this would be equivalent to moving the circle 1 unit to the right, which would make the smallest value 0 and the greatest value 2. But this isn't the correct answer. So what does |z-1| actually mean in comparison to the locus you're initially given?
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    (Original post by DJMayes)
    Yes. You're looking for  \dfrac{P(4<T<6)}{P(T>4)}

    There is another way to look at it - you know more than four minutes have been spent at the till, and that the probability of her stopping at any given time is equally likely. Using this, you can write the amount of time extra she spends as another uniform distribution - in this case, as you know there are 5 minutes left (She spends at most 5 minutes) and she is equally likely to stop at any given time, so you can write the amount of extra time she spends as a uniform distribution between 0 and 5 and solve this way.
    Interesting I may try that method! Thanks DJ
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    (Original post by brittanna)
    Can someone help me with this question:

    The point P represents a complex number z in an Argand diagram. Given that  |z+1-i|=1, find the greatest and least values of |z-1|.

    I thought that this would be equivalent to moving the circle 1 unit to the right, which would make the smallest value 0 and the greatest value 2. But this isn't the correct answer. So what does |z-1| actually mean in comparison to the locus you're initially given?
    You're told that the distance from your variable point z to the point -1+i is fixed at 1. This is essentially the definition of a circle - the locus of points a fixed distance away from a certain point. Now, you want to find the point on this locus which is the furthest away from 1, as this is what |z-1| represents - the distance in the argand diagram between z and 1. Does this help?
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    (Original post by Skaterkid)




    Can this frame be used for edexcel hypothesis testing to get full marks? I think this under OCR S2 so I have no idea.
    anyone?
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    (Original post by Skaterkid)
    anyone?
    Seems like a good frame but don't forget the conclusion (and obviously the probability calculation given that the null hypothesis is true). For Edexcel the null hypothesis can be modelled by Poisson/Normal distribution too but I'm not sure about OCR sorry.
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    (Original post by reubenkinara)
    Attachment 217104Here's a solution scan from my textbook (Edexcel AS and A level Modular Mathematics) on interpolation Hopefully the yellow boxes and the text within the example are sufficient without the actual question and its data!
    Ok, thank you, I get the idea.
    I just don't know if it is the method I should use, I looked in my textbook, and there isn't anything like that in it.
    Have to ask my teacher on Monday.
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    (Original post by reubenkinara)
    I see. Good luck then
    thanks goodluck to you too
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    (Original post by purplemind)
    Ok, thank you, I get the idea.
    I just don't know if it is the method I should use, I looked in my textbook, and there isn't anything like that in it.
    Have to ask my teacher on Monday.
    Are you on a different exam board or something. I thought the S1 exams were over with
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    Stupid me and my Assumptions!
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    (Original post by DJMayes)
    You're told that the distance from your variable point z to the point -1+i is fixed at 1. This is essentially the definition of a circle - the locus of points a fixed distance away from a certain point. Now, you want to find the point on this locus which is the furthest away from 1, as this is what |z-1| represents - the distance in the argand diagram between z and 1. Does this help?
    Thank you!

    Remind me to rep you if I forget as I have run out for now.

    And I decided that the mechanics questions in STEP aren't really the thing for me .
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    (Original post by reubenkinara)
    Are you on a different exam board or something. I thought the S1 exams were over with
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    Stupid me and my Assumptions!
    Yes, I'm doing OCR. So S1 is on Friday.
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    (Original post by purplemind)
    Yes, I'm doing OCR. So S1 is on Friday.
    I see. That's when I have C2 and others have S2 (Edexcel). OCR, non MEI?
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    (Original post by reubenkinara)
    I see. That's when I have C2 and others have S2 (Edexcel). OCR, non MEI?
    Non MEI.
    You see, I had C2 yesterday.
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    (Original post by brittanna)
    Thank you!

    Remind me to rep you if I forget as I have run out for now.

    And I decided that the mechanics questions in STEP aren't really the thing for me .
    Sorry to intrude but I'd suggest you atleast learn the equation for a projectile as they tend to be very nice questions and a good way of getting some high marks, as suggested by DJMayes himself you just need to use the discriminant and able to manipulate the algebra in the question. They tend to be the only mechanics question I try but still it'll be another 15-20 marks which could be crucial in me getting my offer for Warwick


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    (Original post by MathsNerd1)
    Sorry to intrude but I'd suggest you atleast learn the equation for a projectile as they tend to be very nice questions and a good way of getting some high marks, as suggested by DJMayes himself you just need to use the discriminant and able to manipulate the algebra in the question. They tend to be the only mechanics question I try but still it'll be another 15-20 marks which could be crucial in me getting my offer for Warwick


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    I spent today trying to do some applied questions (mainly mechanics), and they just weren't coming to me. All this means for me is that i'm not going to spend much time before the exam going over the mechanics questions. But I did go over the equation, so I guess that if one does come up in the exam, then I could make an attempt at it (although I doubt that attempt will last more than 5 minutes .)
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    (Original post by brittanna)
    I spent today trying to do some applied questions (mainly mechanics), and they just weren't coming to me. All this means for me is that i'm not going to spend much time before the exam going over the mechanics questions. But I did go over the equation, so I guess that if one does come up in the exam, then I could make an attempt at it (although I doubt that attempt will last more than 5 minutes .)
    I see well at least don't completely rule them out as they honestly can be some nice marks to get in the actual exam, with that being said I've completely ruled out the Stats questions as its been far too long since I practiced any of the methods so I wouldn't know where to start with them. I feel like I should try more of the Mechanics questions as some of them can be easier than some pure questions which could be touch and go with me at the minute, but we shall see how it goes on the day

    Also while on the topic how is your preparation coming along for STEP, AEA and all your other Maths exams?
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    can someone tell me the definition of a many to one function please?
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    Could anyone help me with Q9a please from this C2 paper?

    I don't know how to work out the formulae for the volume and area of a right prism with a circle sector at the top and online searches haven't really helped. Thanks
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    (Original post by Endless Blue)
    Could anyone help me with Q9a please from this C2 paper?

    I don't know how to work out the formulae for the volume and area of a right prism with a circle sector at the top and online searches haven't really helped. Thanks
    2 surfaces are sectors of circles

    2 are rectangles of height h and width r.

    The last bit is essentially a rectangle of height h, and the width would be the length of the arc of the circle sector, if that makes sense.

    So just add them all up.
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    (Original post by justinawe)
    2 surfaces are sectors of circles

    2 are rectangles of height h and width r.

    The last bit is essentially a rectangle of height h, and the width would be the length of the arc of the circle sector, if that makes sense.

    So just add them all up.
    Ah, ok, that makes sense. So is A= 3rh + r^2 correct?
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    (Original post by JenniS)
    can someone tell me the definition of a many to one function please?
    Many to one is where two or more elements in the domain can be mapped onto the same element in the range e.g. consider the graph of y=x^2 if you have the domain (input values): -1, 1, -2, 2, -3, 3 the range (output) will be: 1 (for both -1 and 1), 4 (for -2 and 2) and 9 (for -3 and 3).
 
 
 
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