Hey there! Sign in to join this conversationNew here? Join for free

Edexcel Core 3 - 21st June 2016 AM Watch

Announcements
    • Very Important Poster
    Online

    21
    ReputationRep:
    (Original post by pineneedles)
    Thanks 😊 Im not sure if this is clear enough, not used to working with arcsin etc :
    Attachment 548183

    Posted from TSR Mobile
    4/4 marks :borat: (I wonder what that thing is in the background though :lol:)
    Offline

    19
    ReputationRep:
    By the way, as my offers post exams are always missed amongst the flood of posts, if anyone somehow would have access to this paper (same goes for C4, probs don't remember most remaining applied modules well enough though) on the day I'd be happy to do solutions. Not exactly necessary because probs Zacken and kprime will have some done soon after as well but me being a no-life I'm sure with access to the paper I could have things down fairly soon after the exam lol.
    Offline

    11
    ReputationRep:
    (Original post by SeanFM)
    4/4 marks :borat: (I wonder what that thing is in the background though :lol:)
    Great, and that's an owl on my duvet :yep:

    Posted from TSR Mobile
    Offline

    2
    ReputationRep:
    (Original post by 13 1 20 8 42)
    By the way, as my offers post exams are always missed amongst the flood of posts, if anyone somehow would have access to this paper (same goes for C4, probs don't remember most remaining applied modules well enough though) on the day I'd be happy to do solutions. Not exactly necessary because probs Zacken and kprime will have some done soon after as well but me being a no-life I'm sure with access to the paper I could have things down fairly soon after the exam lol.
    For FP2, Zacken had to wait 24 hours to get access to the paper, IDK about kprime. So if you are able to get access to the papers before the 24 hours then anyone on the forum would be extremely happy and eternally grateful, but I'm doubting you'll be able to.
    Offline

    19
    ReputationRep:
    (Original post by Craig1998)
    For FP2, Zacken had to wait 24 hours to get access to the paper, IDK about kprime. So if you are able to get access to the papers before the 24 hours then anyone on the forum would be extremely happy and eternally grateful, but I'm doubting you'll be able to.
    Fair enough, I wouldn't expect it. I'll be back home by then, maybe I can nip to my old school for one..
    Offline

    3
    ReputationRep:
    (Original post by 13 1 20 8 42)
    Fair enough, I wouldn't expect it. I'll be back home by then, maybe I can nip to my old school for one..
    Yep. Zacken and Kprime get it 24 hours after the exam. You could ask them whether or not you could do one of the papers, certainly would be interesting!
    Offline

    19
    ReputationRep:
    (Original post by Ayman!)
    Yep. Zacken and Kprime get it 24 hours after the exam. You could ask them whether or not you could do one of the papers, certainly would be interesting!
    My Year 13 maths teacher was pretty relaxed, I'm sure if I just go in unannounced and ask for a C3 paper I can get one...
    Offline

    14
    ReputationRep:
    (Original post by Ayman!)
    Yep. Zacken and Kprime get it 24 hours after the exam. You could ask them whether or not you could do one of the papers, certainly would be interesting!
    how do you get the papers? are they available on the edexcel hidden teachers section?
    Offline

    7
    ReputationRep:
    (Original post by pineneedles)
    Attachment 548013
    f(x) = k
    So f(x) - k = 0
    K transforms f(x) by shifting it down by k units. We need to find the value of k which will mean f(x) will intersect with the x axis in two places. In the graph I've attached, if k is 1, the graph will have one root, meaning that as long as k > 1, the function will have two roots.
    Another poster said you could do it using the discriminant, and you could, but this is how you would do it if you don't actually have f(x), and you just have a graph as some questions I've seen. I'll try and find an example and edit this post.

    Posted from TSR Mobile
    Ohh now i get it. thanks so much! so if it asks for when k has one root. then thats k=1. If it asks for when k has no roots then k< 1. is that correct?
    Offline

    2
    ReputationRep:
    Do we have to know any proofs for this module ?


    Posted from TSR Mobile
    Offline

    11
    ReputationRep:
    (Original post by Lilly1234567890)
    Ohh now i get it. thanks so much! so if it asks for when k has one root. then thats k=1. If it asks for when k has no roots then k< 1. is that correct?
    Not generally speaking, no, that only applies to the graph I've posted. The idea though applies to any curve. You're just looking for the translation which will cause the curve to intersect with the x axis in two places. I'll get another graph, see if you can apply that idea to another curve entirely.

    Posted from TSR Mobile
    Offline

    2
    ReputationRep:
    (Original post by SeanFM)
    Not simultaneously - try applying them both to the original to the equation, one at a time.
    I managed to do it but I'm not sure if my method makes sense...

    So since arcsinx = arccosy, I said

    Sin[arccosy] = x
    and
    Cos[arcsinx] = y

    Then I said

    Sin[arcsinx] = x
    and
    Cos[arcsinx] = y

    Using the identity sin2x + cos2x = 1,

    Sin2[arcsinx] + Cos2[arcsinx] = 1

    Therefore it follows that:

    x2 + y2 = 1.

    Would I still get the marks for this? I guess I kinda did what you guys did but in a roundabout kind of way xD
    • Very Important Poster
    Online

    21
    ReputationRep:
    (Original post by Don Pedro K.)
    I managed to do it but I'm not sure if my method makes sense...

    So since arcsinx = arccosy, I said

    Sin[arccosy] = x
    and
    Cos[arcsinx] = y

    Then I said

    Sin[arcsinx] = x
    and
    Cos[arcsinx] = y

    Using the identity sin2x + cos2x = 1,

    Sin2[arcsinx] + Cos2[arcsinx] = 1

    Therefore it follows that:

    x2 + y2 = 1.

    Would I still get the marks for this? I guess I kinda did what you guys did but in a roundabout kind of way xD
    That's how we did it just more rigourously.
    Offline

    7
    ReputationRep:
    (Original post by pineneedles)
    Not generally speaking, no, that only applies to the graph I've posted. The idea though applies to any curve. You're just looking for the translation which will cause the curve to intersect with the x axis in two places. I'll get another graph, see if you can apply that idea to another curve entirely.

    Posted from TSR Mobile
    ahh okay i think i get it
    Offline

    2
    ReputationRep:
    (Original post by 13 1 20 8 42)
    My Year 13 maths teacher was pretty relaxed, I'm sure if I just go in unannounced and ask for a C3 paper I can get one...
    Dont teachers need to wait 24 hours before they can get it too?
    Offline

    19
    ReputationRep:
    (Original post by boyyo)
    Dont teachers need to wait 24 hours before they can get it too?
    I dunno. Either way, I was never actually gonna do that..
    Although actually I think I recall I was having a dispute after the FP1 exam with someone because she and I got different answers and seemed to remember the question being slightly different and we went like thirty minutes after the exam and were able to look at a paper.
    Offline

    19
    ReputationRep:
    (Original post by jkhan9625)
    Do we have to know any proofs for this module ?


    Posted from TSR Mobile
    None really. Most proof questions will be trig ones e.g. prove the formula for tan2x.
    Offline

    2
    ReputationRep:
    (Original post by 13 1 20 8 42)
    I dunno. Either way, I was never actually gonna do that..
    Although actually I think I recall I was having a dispute after the FP1 exam with someone because she and I got different answers and seemed to remember the question being slightly different and we went like thirty minutes after the exam and were able to look at a paper.
    Lol. That should be ok then
    Offline

    2
    ReputationRep:
    https://b3755649dbd1afe3db91a899c3b9...%20Edexcel.pdf

    Can someone help me with q2b here. Im not getting the right answer when I do long division and I dont quite understand what the mark scheme does
    Thanks
    • Community Assistant
    • Thread Starter
    Offline

    18
    ReputationRep:
    (Original post by boyyo)
    https://b3755649dbd1afe3db91a899c3b9...%20Edexcel.pdf

    Can someone help me with q2b here. Im not getting the right answer when I do long division and I dont quite understand what the mark scheme does
    Thanks
    Use the Factor theorem for the numerator.
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    How are your GCSEs going so far?
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Quick reply
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.