• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

What raw marks in extension 2 generally correspond to state ranks? (2 Viewers)

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
Well, our school has compulsory participation in the Australian Maths Comp for yr 7 and 8. I did it in yr 7 and got 131/135, which was equivalent to a medal (top 0.03% or smth), and was invited to the Australian School of Excellence. This is a maths camp designed specifically for ppl who are likely to go well in comp maths and train them for the IMO team. Have a look at the AMT website for more info about it.
Lol nice, I didn't know it went that deep. Highest I've ever gotten on it was high distinction in year 8 or something, and have only ever gotten credits/distinctions since then. I'm angry about the one this year though, the website kept crashing for us and there were like at least 3 of the last 5 questions that I could have done. I really hate the tests though, have never really been good at them. If there are kids like you out there doing the extension 2 paper though, I feel like its impossible for me to get a state rank haha.
 

Carrotsticks

Retired
Joined
Jun 29, 2009
Messages
9,494
Gender
Undisclosed
HSC
N/A
Hopefully this year's last question doesn't prevent potential state-rankers from doing their best like last year's silly geometry question.
 

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
Hopefully this year's last question doesn't prevent potential state-rankers from doing their best like last year's silly geometry question.
Yeah I hated that geometry question. It shows how bad some recent years have gotten in ext 2, either having easy Q16s (2014, 2017) or artificially difficult ones (2018). If you compare to like 2001 or even 2010, which had some really genuinely difficult questions, it is obvious how uninspired they have gotten. In fact the only post 2012 paper I thought was good was 2016, and even that wasn't great until Q16. Oh well, hopefully 2019 will be a bit better haha, since it is the last year.
 

HeroWise

Active Member
Joined
Dec 8, 2017
Messages
353
Gender
Male
HSC
2020
Hopefully. But could be harder too. Especially for things like conics, probs that might be this years q16 which are getting remvd.
 

UStoleMyBike

New Member
Joined
Mar 7, 2018
Messages
17
Gender
Undisclosed
HSC
2019
Uni Grad
2023
There hasn't been a tricky integral in a couple of years, I feel like we are due for a hard integration question
 

DrEuler

Member
Joined
Jul 7, 2018
Messages
73
Gender
Male
HSC
N/A
There hasn't been a tricky integral in a couple of years, I feel like we are due for a hard integration question
We all know what happened the last time they tried that *2014 HSC*. All the top students/state ranks literally did it in two steps because it could be done by inspection.

So na after that disaster I don't think they will haha
 

idkkdi

Well-Known Member
Joined
Aug 2, 2019
Messages
2,573
Gender
Male
HSC
2021
Well, our school has compulsory participation in the Australian Maths Comp for yr 7 and 8. I did it in yr 7 and got 131/135, which was equivalent to a medal (top 0.03% or smth), and was invited to the Australian School of Excellence. This is a maths camp designed specifically for ppl who are likely to go well in comp maths and train them for the IMO team. Have a look at the AMT website for more info about it.
Did you end up making IMO?
 

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
We all know what happened the last time they tried that *2014 HSC*. All the top students/state ranks literally did it in two steps because it could be done by inspection.

So na after that disaster I don't think they will haha
I think we could possibly have an integral similar to one of the ones we see in the integration marathons here, but that may be too hard for most 4u students. 2014 one was hilarious.
 

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
Never really saw the point of doing those convoluted integral questions. 99% of it is spent doing algebraic manipulations rather than actual integrating, which is kinda pointless.
Yeah thats probably true. I personally enjoy the algebraic manipulations, I find the problem solving aspect quite interesting but yeah they aren't very good mathematically. When you have stupid stuff like the geometry question last year though it wouldn't be surprising for the last question to just be one of these convoluted algebraic manipulations.
 

Drdusk

Moderator
Moderator
Joined
Feb 24, 2017
Messages
2,022
Location
a VM
Gender
Male
HSC
2018
Uni Grad
2023
I haven't seen it, but yeh the same logic applies, ridiculous convoluted geometry questions are also kinda pointless. In fact.... any ridiculous convoluted question is kinda pointless... which why I cheered when they scrapped conics.
Forget convoluted geometry questions

NESA when thinking of an actually good question 15 for the 2018 HSC:



This one was soo convoluted
 

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
Forget convoluted geometry questions

NESA when thinking of an actually good question 15 for the 2018 HSC:



This one was soo convoluted
Lol completely forgot about that. What a ridiculous question. It wasn't even difficult, just a standard de moivrre's theorem identity, but god it took ages just because of all the algebra. 2018 in general had a lot of really stupid convoluted questions.
 

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
I haven't seen it, but yeh the same logic applies, ridiculous convoluted geometry questions are also kinda pointless. In fact.... any ridiculous convoluted question is kinda pointless... which why I cheered when they scrapped conics.
Yeah conics is mostly garbage, although there have been a few decent questions, such as the 2000 one near the end of the paper (7b iirc), as well as the 2005 one, but even that was convoluted, it just required more mathematical reasoning than algebra. I honestly think the nicest topic in 4u is polynomials, even if 90% of the time those questions are dead easy.
 

fan96

617 pages
Joined
May 25, 2017
Messages
543
Location
NSW
Gender
Male
HSC
2018
Uni Grad
2024
Forget convoluted geometry questions

NESA when thinking of an actually good question 15 for the 2018 HSC:



This one was soo convoluted
Honestly, that question was more annoying than all of Q16 put together.
 

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
Yeh the entire conics chapter was useless. It was all just algebra and didn't contain anything new. The topic itself is also useless in the sense that it finds very little application in the real world. The only thing that I can think of is in trajectory calculations, and even then it doesn't really require all that much. My fav topic in 4u is mechanics since it's the only topic that actually applies the math to real world situations. Volumes is also nice too in that it's the only topic that demonstrates how an integral is used to build up a sum from its infinitesimal parts (a fact which they don't really teach), which is an important concept in physics/engineering. Complex numbers and integration are also pretty useful. Every other topic is more or less useless or nice-to-know.
Oh yeah I forgot about mechanics and volumes lol. Volumes is fun but my problem with it is that almost every question is the same. When there is a hard one though its really good. Mechanics is also fun but I generally only like the circular motion bit, the reaisted motion is literally the same thing every time: equation for acceleration, then integrate to get v in terms of t, sometimes incorporating terminal veloicty. There was a really good resisted motion problem in one of the BOS trials though where there was resisted SHM and you had to solve a second order linear differential equation (but it gave you the integrating factor and basically told you how to do it). Makes me wish differential equations were in the 4u syllabus, would make mechanics so much better. I reckon taylor series could also be in the syllabus instead of something like conics or graphs.
 
Last edited:

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,401
Gender
Male
HSC
2006
Speaking of BoS trials....

*cough* *cough*
 

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
Speaking of BoS trials....

*cough* *cough*
I do kind of want to do the BOS trial this year, but I am unfortunately outside of Sydney so it is a hassle to go up to do it. The past papers I have done from it have been quite a good challenge though (I think I've done 2018, 2017, 2015).
 

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
I think the main reason why Taylor series wouldn't be taught is because of the baggage that comes with it. Deriving the basic Taylor series is straightforward, but things like the remainder term, error bounds, radius of convergence (in the context of complex analysis) etc is more indepth that requires more than a surface understanding, and teaching that would feel somewhat out-of-place compared to the straightforwardness of all the other topics. Students don't even know the epsilon-delta definition of a limit, which is typically where you start with undergrad calculus. Likewise with ODE's: solving linear second-order ODE's is straightforward, but typically ODE's are paired with linear algebra, which students don't know.

Also, do you remember the SHM ODE? I'm curious, since I've never really seen integrating factors used to solve second-order ODE's, only in first-order ODE's.
Here is the question:
I remembered it slightly wrong, it basically involves making a substitution of y=v + nx to make it a first order seperable equation and then solving the remaining first order differential equation in x using an integrating factor, which it basically gives to you. I guess its basically like how you would solve a second order homogeneous linear equation without knowing how to use the characteristic equation. I still thought it was a pretty cool way to incorporate differential equations.
 

Attachments

TheOnePheeph

Active Member
Joined
Dec 13, 2018
Messages
241
Gender
Male
HSC
2019
Ah right, yeh so you break down the second-order ODE to a first-order ODE before using the integrating factor - that makes more sense. Is the integrating factor necessary though? The solution to y' + ny = 0 is simply just y = y0*exp(-nt).
The equation in y doesn't need an integrating factor, its just seperable, but when you subsitute v + nx back into it you get dx/dt + nx = y0exp(-nt), which does need an integrating factor.
 

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,401
Gender
Male
HSC
2006
Here is the question:
I remembered it slightly wrong, it basically involves making a substitution of y=v + nx to make it a first order seperable equation and then solving the remaining first order differential equation in x using an integrating factor, which it basically gives to you. I guess its basically like how you would solve a second order homogeneous linear equation without knowing how to use the characteristic equation. I still thought it was a pretty cool way to incorporate differential equations.
The resisted SHM question given there was a special case where the roots of the characteristic polynomial were equal. This lends itself to a more 'first principles' approach to solving it in a nice way without calling upon any ODE specific theory.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 2)

Top