Page 5 of 5 FirstFirst ... 345
Results 101 to 112 of 112
Like Tree107Likes

Thread: BoS Maths Trials 2017

  1. #101
    New Member
    Join Date
    Sep 2017
    HSC
    2017
    Gender
    Male
    Posts
    8
    Rep Power
    1

    Re: BoS Maths Trials 2017

    >dying at someone getting 8/15 congrats Calamebe
    Did a little worse than I thought, 50/58 for the marks I attempted. *shrugs* thanks for your time though everyone!
    calamebe likes this.

  2. #102
    New Member
    Join Date
    Jun 2016
    HSC
    N/A
    Gender
    Male
    Posts
    9
    Rep Power
    2

    Re: BoS Maths Trials 2017

    Quote Originally Posted by Paradoxica View Post
    aye lmao apparently people think



    rip there goes ur marks

    also

    a lot of people forgot that √k = 1-√h

    their area function was (1-√h)² instead of (1-√h)⁴

    there goes another mark

    bless u janzen choi for being the one person who got my spiky volume correct <3

    another kid almost got the answer correct but they forgot to double the result bc they were only finding the upper half volume...

    rip in pieces

    also a lot of u stoners thought the curved edges were like a square minus a circle????

    can u even graphs plz
    <3 back
    Carrotsticks and Paradoxica like this.

  3. #103
    Administrator Trebla's Avatar
    Join Date
    Feb 2005
    HSC
    2006
    Gender
    Male
    Posts
    6,052
    Rep Power
    20

    Re: BoS Maths Trials 2017

    Updated the solutions to cover typos that were drawn to my attention.

    Also, a particular point of feedback on one of the questions I marked. Far too many students actually did not attempt Q15b)iii) which should have been a free mark, especially if you're familiar with these types of questions. A surprising number of students actually wrote the limit was 1 despite the sum showing that it is clearly larger than 1.

    On the flip side it was good to see a handful of students manage to get out Q15b)i) using a direct geometric series approach (which is often quite obscure to recognise) instead of the typical reduction formula approach which also would have worked.

    Another point to make is Q11d), some were using inequalities with the complex numbers themselves rather than the modulus (which is a real number). You cannot create inequalities between complex numbers! You can only create inequalities describing something like their modulus or argument (which are real values).

    Also, Q11a) gg so many people got owned by that integral...
    Last edited by Trebla; 22 Oct 2017 at 6:17 PM.

  4. #104
    Supreme Member seanieg89's Avatar
    Join Date
    Aug 2006
    HSC
    2007
    Gender
    Male
    Posts
    2,680
    Rep Power
    10

    Re: BoS Maths Trials 2017

    I think the Q16h solution is still not quite correct.

    Whilst it is true that

    x-k\alpha =< x for each x, we cannot simply bound the product of factors of this form by the product of the x's, as some of these terms will in general be negative.

    Another way of seeing this problem is that if we take absolute values and k\alpha happens to be close to n, then we see that in fact the early terms in this product are the largest, (but the inequality is still true because the later terms in the product are small).

  5. #105
    -insert title here- Paradoxica's Avatar
    Join Date
    Jun 2014
    HSC
    2016
    Gender
    Male
    Location
    Outside reality
    Posts
    2,417
    Rep Power
    4

    Re: BoS Maths Trials 2017

    Quote Originally Posted by Trebla View Post
    Also, Q11a) gg so many people got owned by that integral...
    Oh come on, it wasn't THAT hard....

    :P
    If I am a conic section, then my e = ∞

    Just so we don't have this discussion in the future, my definition of the natural numbers includes 0.

  6. #106
    Junior Member aycaramba's Avatar
    Join Date
    Aug 2015
    HSC
    N/A
    Gender
    Female
    Posts
    126
    Rep Power
    2

    Re: BoS Maths Trials 2017

    Well, good luck for tomorrow everybody - let's smash it

  7. #107
    Cadet
    Join Date
    Nov 2015
    HSC
    N/A
    Gender
    Male
    Posts
    32
    Rep Power
    2

    Re: BoS Maths Trials 2017

    Quote Originally Posted by aycaramba View Post
    Well, good luck for tomorrow everybody - let's smash it
    Yes, good luck indeed. I hope it's easy enough that we don't need it tho :P

  8. #108
    Retired Carrotsticks's Avatar
    Join Date
    Jun 2009
    HSC
    N/A
    Gender
    Undisclosed
    Posts
    9,552
    Rep Power
    20

    Re: BoS Maths Trials 2017

    Quote Originally Posted by seanieg89 View Post
    I think the Q16h solution is still not quite correct.

    Whilst it is true that

    x-k\alpha =< x for each x, we cannot simply bound the product of factors of this form by the product of the x's, as some of these terms will in general be negative.

    Another way of seeing this problem is that if we take absolute values and k\alpha happens to be close to n, then we see that in fact the early terms in this product are the largest, (but the inequality is still true because the later terms in the product are small).
    Hey man, thanks for pointing this out. I've attached a more detailed solution. I got a bit lazy towards the end and also wanted to keep it within 2 pages, but I think this should do the trick. I was supposed to write the Q16 solutions on Sat night but I̶ ̶w̶e̶n̶t̶ ̶t̶o̶ ̶E̶l̶ ̶J̶a̶n̶n̶a̶h̶ ̶a̶n̶d̶ ̶c̶h̶i̶l̶l̶e̶d̶ ̶w̶i̶t̶h̶ ̶m̶a̶t̶e̶s̶ ̶t̶i̶l̶l̶ ̶1̶a̶m̶ ̶i̶n̶s̶t̶e̶a̶d̶ I didn't have time to do them, so this one's on me.

    Correction.pdf
    Paradoxica likes this.

  9. #109
    Cadet
    Join Date
    Nov 2015
    HSC
    N/A
    Gender
    Male
    Posts
    32
    Rep Power
    2

    Re: BoS Maths Trials 2017

    Hey Guys,

    Just wondering around what time you think the 3U solutions will be released?
    phopo likes this.

  10. #110
    Administrator Trebla's Avatar
    Join Date
    Feb 2005
    HSC
    2006
    Gender
    Male
    Posts
    6,052
    Rep Power
    20

    Re: BoS Maths Trials 2017

    Boom
    Attached Files Attached Files

  11. #111
    New Member
    Join Date
    Jun 2017
    HSC
    2017
    Gender
    Male
    Posts
    5
    Rep Power
    1

    Re: BoS Maths Trials 2017

    cheers

  12. #112
    I love trials pikachu975's Avatar
    Join Date
    May 2015
    HSC
    2017
    Gender
    Male
    Location
    NSW
    Posts
    2,055
    Rep Power
    3

    Re: BoS Maths Trials 2017

    Oh wow 28 lol did better than I expected
    Offering tutoring for Biology, Maths, Maths Ext 1, and Maths Ext 2.

    Solar Education - CHEAP Quality Tutoring

    Buy my books/notes cheaply here!

    --------------------------------------------------------------------------------

    2016 HSC (Accelerated): // 2U Maths (97) // SOR 1 (48) //
    2017 HSC: // English Adv (91) // Bio (96) // Phys (95) // 3U Maths (99) // 4U Maths (97) //
    ATAR: 99.75

Page 5 of 5 FirstFirst ... 345

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •