Turn on thread page Beta
    Offline

    22
    ReputationRep:
    (Original post by Chirstos Ioannou)
    Could someone explain 6 (ii) (a)

    Attachment 534809

    Attachment 534809534811
    Pull out a factor of 1/2 (or -1/2) and you should see that the remianing bit inside the bracket is rotation of angle 30 (or 60)
    Offline

    2
    ReputationRep:
    Where can I find the mark scheme?
    Offline

    11
    ReputationRep:
    I've given up on that area of a triangle question
    Offline

    16
    ReputationRep:
    (Original post by Zacken)
    Pull out a factor of 1/2 (or -1/2) and you should see that the remianing bit inside the bracket is rotation of angle 30 (or 60)
    ii A is just finding the Det M, because the det is the scale factor, so ii (a) is 4, isn't it? Aren't you talking about part ii (b)?
    Offline

    11
    ReputationRep:
    (Original post by iMacJack)
    This

    It was really difficult for an area of a triangle question...

    Maybe kingaaran will help us!
    Isn't it just two right-angled triangles? Because the two points P and Q have the same x coordinate so you can have 2 right angled triangles by splitting it up at the X axis?
    Offline

    2
    ReputationRep:
    (Original post by Zacken)
    Pull out a factor of 1/2 (or -1/2) and you should see that the remianing bit inside the bracket is rotation of angle 30 (or 60)
    I didn't get it at all.

    Name:  235.png
Views: 52
Size:  7.2 KB
    Offline

    22
    ReputationRep:
    (Original post by iMacJack)
    ii A is just finding the Det M, because the det is the scale factor, so ii (a) is 4, isn't it? Aren't you talking about part ii (b)?
    Huh, I guess you could do it that way. I just noticed that if pulled an factor of -1/2 out I'm left with a simple rotation inside.
    Offline

    7
    ReputationRep:
    For that PQS question, I found an area formula which helped me work it out..

    (I have attached it as an image but the source is http://www.mathopenref.com/coordtrianglearea.html)

    So A is (3, 0)
    B is (12, 12)
    and C is (27, -18)

    Ax=3, Ay=0
    Bx=12, By=12
    Cx=27, Cy=-18

    Subbing those into the formula, I got 225 units^2

    Honestly though, I tried drawing diagrams and everything...couldn't find a better way of doing it tbh
    Attached Images
     
    Offline

    16
    ReputationRep:
    (Original post by Zacken)
    Pull out a factor of 1/2 (or -1/2) and you should see that the remianing bit inside the bracket is rotation of angle 30 (or 60)
    I don't understand why you'd pull out a factor of a half?
    Offline

    16
    ReputationRep:
    (Original post by Zacken)
    Huh, I guess you could do it that way. I just noticed that if pulled an factor of -1/2 out I'm left with a simple rotation inside.
    Yeah I know - I mean didn't he ask for help on part (a), which is the scale factor?
    Offline

    1
    ReputationRep:
    Hey does anyone have any predictions for this year? Cheers
    Offline

    22
    ReputationRep:
    (Original post by iMacJack)
    Yeah I know - I mean didn't he ask for help on part (a), which is the scale factor?
    Urgh, sorry. I meant pull out a factor of 2. Then you get 2(rotation matrix) so the 2 is your scale factor.
    Offline

    2
    ReputationRep:
    (Original post by Zacken)
    Pull out a factor of 1/2 (or -1/2) and you should see that the remianing bit inside the bracket is rotation of angle 30 (or 60)
    How would u know to pull out half
    Offline

    7
    ReputationRep:
    (Original post by TheRandomGenius)
    I've given up on that area of a triangle question
    I found a solution which might help, somewhere on page 46 of this thread :P (I hope you're talking about the PQS question lol)

    (Yeah look a couple of posts above this one)
    Offline

    9
    ReputationRep:
    (Original post by economicss)
    Could anyone show how to do question 14 please http://crashmaths.com/wp-content/upl...-Worksheet.pdf really hard coordinate systems question, thanks!
    That is a beastly question haha!! Just done the first part now! How far have you got?
    Offline

    10
    ReputationRep:
    Anyone tried 2014 June R? I think it's a good paper tbh.
    Offline

    11
    ReputationRep:
    6b anyone? (i and ii). I've gone around in circles and ended up in an algebraic mess.

    https://7cba9babeb0db0ff9468853e0b2d...%20Edexcel.pdf
    Offline

    11
    ReputationRep:
    (Original post by WhatIsSleep)
    For that PQS question, I found an area formula which helped me work it out..

    (I have attached it as an image but the source is http://www.mathopenref.com/coordtrianglearea.html)

    So A is (3, 0)
    B is (12, 12)
    and C is (27, -18)

    Ax=3, Ay=0
    Bx=12, By=12
    Cx=27, Cy=-18

    Subbing those into the formula, I got 225 units^2

    Honestly though, I tried drawing diagrams and everything...couldn't find a better way of doing it tbh
    I don't understand, isn't it like two right angled triangles which you can use 1/2 base times height with?

    I tried drawing it, obviously I've drawn it very inaccurately (terrible paint skills) since it doesn't look like a normal but is it something like this? Might be wrong. Sorry if I'm completely wrong with how it looks.
    This gets 225 anyway.
    Offline

    9
    ReputationRep:
    Just to check when rearranging matrices does the term always go to the front so if
    AB=C

    A=B-1C

    and
    B=A-1C

    Or is this wrong? it looks wrong
    Offline

    16
    ReputationRep:
    (Original post by TheMoon)
    I don't understand, isn't it like two right angled triangles which you can use 1/2 base times height with?

    I tried drawing it, obviously I've drawn it very inaccurately (terrible paint skills) since it doesn't look like a normal but is it something like this? Might be wrong. Sorry if I'm completely wrong with how it looks.
    This gets 225 anyway.
    Should be (12,12) not (27,12)
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: August 18, 2016

University open days

  1. University of Cambridge
    Christ's College Undergraduate
    Wed, 26 Sep '18
  2. Norwich University of the Arts
    Undergraduate Open Days Undergraduate
    Fri, 28 Sep '18
  3. Edge Hill University
    Faculty of Health and Social Care Undergraduate
    Sat, 29 Sep '18
Poll
Which accompaniment is best?

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.