Turn on thread page Beta

OCR C2 non-mei 23rd May 2018 Unofficial Markscheme watch

    • Thread Starter
    Offline

    22
    ReputationRep:
    Discuss your answers.

    I managed to do the show that log question.

    For 9 is a 2 or 4
    Offline

    6
    ReputationRep:
    I’ve been told by friends that a = 2. Didn’t get anywhere close to that myself but I spent more time crying about the paper than answering questions
    • Thread Starter
    Offline

    22
    ReputationRep:
    (Original post by bethanngreen)
    I’ve been told by friends that a = 2. Didn’t get anywhere close to that myself but I spent more time crying about the paper than answering questions
    Yah I feel you.

    I got a =4 for some weird reason...
    Posted on the TSR App. Download from Apple or Google Play
    Offline

    6
    ReputationRep:
    When I was integrating I kept getting 1/2 a in my answers so might be something to do with that??
    (Original post by Bulletzone)
    Yah I feel you.

    I got a =4 for some weird reason...
    Offline

    15
    ReputationRep:
    Pretty sure a = 2,
    I used simultaneous equations with the f(x) and the integration of that to eliminate c at the very end.
    Question 8 was very fiddly though so I imagine there would be quite a few method marks.
    Offline

    10
    ReputationRep:
    (Original post by humanteaparty)
    Pretty sure a = 2,
    I used simultaneous equations with the f(x) and the integration of that to eliminate c at the very end.
    Question 8 was very fiddly though so I imagine there would be quite a few method marks.
    Yep simultaneous equations and got a = 2 as well. Agree with method marks. Plenty of places to slip up on that question.

    Also OP, pretty sure the question with a was question 8 not 9?
    Offline

    15
    ReputationRep:
    Also got a =2, integrate once and rearrange to make C the subject so you get something like c = a/2 + 3 then sub that in and integrate once more.
    Sub the limits in and keep going till your down to a/3 + 20 or whatever it was then equate that to 30 and solve for a
    Offline

    7
    ReputationRep:
    I thought the paper was easier than previous papers so I expect grade boundaries to be high. The question I found most confusing was the sum to infite question for the geometric sequence. What did everyone get for that?
    • Thread Starter
    Offline

    22
    ReputationRep:
    (Original post by tislam1)
    I thought the paper was easier than previous papers so I expect grade boundaries to be high. The question I found most confusing was the sum to infite question for the geometric sequence. What did everyone get for that?
    u1 =20
    u2 = 20(0.8)
    u3 = 20(0.8)^2
    u4 = 20(0.8)^3

    Therefore sum to infinity of Sn for u2n = a / (1-r)

    a = u2 and r = u4 ÷ u2
    Posted on the TSR App. Download from Apple or Google Play
    Offline

    4
    ReputationRep:
    (Original post by Bulletzone)
    Discuss your answers.

    I managed to do the show that log question.

    For 9 is a 2 or 4
    Last answer I got x=2, x=4add2root10, x=4-2root10 or something like that. There was definitely a plus or minus 2root10
    Posted on the TSR App. Download from Apple or Google Play
    Offline

    7
    ReputationRep:
    That was the worst paper I’ve every done
    Offline

    4
    ReputationRep:
    (Original post by Bulletzone)
    u1 =20
    u2 = 20(0.8)
    u3 = 20(0.8)^2
    u4 = 20(0.8)^3

    Therefore sum to infinity of Sn for u2n = a / (1-r)

    a = u2 and r = u4 ÷ u2
    That’s exactly what I did!
    u2 = 16
    u4 = 10.24
    r = 0.64
    Sum to Infinity = 16/(1-0.64) = 4.44
    • Thread Starter
    Offline

    22
    ReputationRep:
    (Original post by Finlaycollins)
    That’s exactly what I did!
    u2 = 16
    u4 = 10.24
    r = 0.64
    Sum to Infinity = 16/(1-0.64) = 4.44
    That's the answer have some rep.
    Posted on the TSR App. Download from Apple or Google Play
    Offline

    12
    ReputationRep:
    a=1/2
    Offline

    6
    ReputationRep:
    Shouldn't it be 44.4

    Also what was the answer to the area and r for the triangle and sector of a circle question?
    Offline

    3
    ReputationRep:
    I got sum to infinity to be 400/9As its u2N you get 20x(0.8)^2N-1 So if you put in n=1 you get a=16If you put in n=2 you get it as 10.24R=0.64 Do a sum to infinity you get 400/9Not sure if its right
    Offline

    3
    ReputationRep:
    Got a= -28. Brilliant
    Offline

    3
    ReputationRep:
    9.40 for area
    Offline

    4
    ReputationRep:
    (Original post by aurora0914)
    9.40 for area
    I got the obtuse angle as something around 2.35?
    and part iii) the arc length as 2.69 give or take
    but not 100% sure on it
    • Thread Starter
    Offline

    22
    ReputationRep:
    (Original post by fzzpop)
    i got the obtuse angle as something around 2.35?
    And part iii) the arc length as 2.69 give or take
    but not 100% sure on it
    ffs i forgot to do (pi) - angle
    Posted on the TSR App. Download from Apple or Google Play
 
 
 

University open days

  1. University of Bradford
    University-wide Postgraduate
    Wed, 25 Jul '18
  2. University of Buckingham
    Psychology Taster Tutorial Undergraduate
    Wed, 25 Jul '18
  3. Bournemouth University
    Clearing Campus Visit Undergraduate
    Wed, 1 Aug '18
Poll
How are you feeling in the run-up to Results Day 2018?

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

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