Predictions (1 Viewer)

[scaryshark09]

Predictions for every single math question in the 4u paper this year?

 

[carrotsss]

I bet there will be at least 1 mark on complex numbers

 

[SadCeliac]

Predictions for every single math question in the 4u paper this year?

im gonna do a copy past mi amor



we've done this already multiple times on BoS, and every time we decide that there's in no point trying to meta the HSC - just prepare everything you think you need, 'predicting' the questions really won't help you <3

may i suggest just look at the syllabus and rubric key terms and then base your study off of that, rather than past essay questions that they "guaranteed won't ask again" because you never know and nothing is ever guaranteed

 

[synthesisFR]

Predictions for every single math question in the 4u paper this year?

4 mark inequality induction please im praying for it

 

[Sam14113]

Quick disclaimer: Just my unqualified opinion - it's fun to guess, but it's really nothing more than that.

Topics:
I've been surprised at the lack of 'atypical induction' questions so far (especially geometric and combinatorial) so I want to think one of those in the next 2 years.

Same goes with resisted projectile motion (tbf there was one multiple choice question in 2022) but the topic is so tedious even a simple question warrants lots of marks, so I think it's quite unattractive to exam writers. I'm a little on the fence though about this one.

Also I haven't checked but I feel like there hasn't been a hard question in the latter part of the complex numbers topic (De Moivre's and roots of unity) --- maybe we're looking to see that come up?

Structure:
Multiple choice questions will follow the trend of being challenging but not long (more so of 3u but I think in 4u as well). NESA website specifically says they want to test understanding and target misconceptions so at most 1 of those stupid trial paper multiple choice questions that would be a 3-marker if it were in the actual paper. NSB2023 Q2 strikes me as an example of something they might ask.

As in 2021 and 2022, the hardest questions will be standalone questions, not scaffolded (though 2020 was scaffolded so you never know right?) and I want to say approximately 2021 difficulty level because last year's paper accrued some criticism.


Oh, and most importantly, the paper will have the year 2023 and the course name 'Mathematics Extension 2' written on the front of the question paper.

 

[SadCeliac]

Oh, and most importantly, the paper will have the year 2023 and the course name 'Mathematics Extension 2' written on the front of the question paper.

Which school paper though

 

[synthesisFR]

Question what would u like to see in q16??!!

 

[SadCeliac]

Question what would u like to see in q16??!!

Preferably a b c d with some questions per letter

 

[Sam14113]

Question what would u like to see in q16??!!

You're going to disagree with me (everyone does) but a geometric induction question would in fact be nice (eg. proving Euler's theorem for planar graphs or polyhedrons).
What I'd really love is a proof by contradiction that tests if you really get what a proof by contradiction is rather than just manipulate numbers around. A classic example would be like a 'strategy stealing' game theory question. But from the syllabus, it seems like this is out of bounds

Other than that, my general hope is just "hard but not too much work". The resisted motion question from last year is awful not because it's hard (it's kind of just solving for a specific variable in a classic resisted motion scenario) but because the answer is like lines and lines and lines and lines of working. I really dislike that. Test me on my maths ability, not my patience.

Besides all of that, I really don't mind what they throw at us.

What about you?

 

[Sam14113]

Preferably a b c d with some questions per letter

Getting to a d is pretty rare tbh

you reckon we can make it this year? I’ve got faith

 

[synthesisFR]

You're going to disagree with me (everyone does) but a geometric induction question would in fact be nice (eg. proving Euler's theorem for planar graphs or polyhedrons).
What I'd really love is a proof by contradiction that tests if you really get what a proof by contradiction is rather than just manipulate numbers around. A classic example would be like a 'strategy stealing' game theory question. But from the syllabus, it seems like this is out of bounds

Other than that, my general hope is just "hard but not too much work". The resisted motion question from last year is awful not because it's hard (it's kind of just solving for a specific variable in a classic resisted motion scenario) but because the answer is like lines and lines and lines and lines of working. I really dislike that. Test me on my maths ability, not my patience.

Besides all of that, I really don't mind what they throw at us.

What about you?

about that resisted question
Would u solve it using two equation of motion for up and down flight or just one?

 

[Sam14113]

about that resisted question
Would u solve it using two equation of motion for up and down flight or just one?

Just one is sufficient but even so you’re setting up the equation, integrating twice and then solving an equation right.

honestly I thought it was worse than it is but compare to 16a which is same number of marks and much shorter solution

EDIT: Oh, and forgot about algebraic rearranging (basically finding the inverse function) to get velocity in terms of time rather than the other way around

 

[synthesisFR]

I haven’t done the paper yet but ive never learnt how to do it with one eqn of motion for vertical motion idk I’ve always learnt to do 2

 

[carrotsss]

Question what would u like to see in q16??!!

one of those big mechanics questions, it’s basically free marks most of the time

 

[synthesisFR]

If there’s anything that looks horrendous I’ll walk out of the exam hall and go to my nearest tafe
I hope it’s not harder than 2021 hsc level tbh

 

[Sam14113]

I haven’t done the paper yet but ive never learnt how to do it with one eqn of motion for vertical motion idk I’ve always learnt to do 2

Ahh let me explain I promise within 30 seconds you’ll get it.

For the sake of discussion, let’s let downwards be positive and upwards be negative (you can reverse if you like but I prefer it this way cos gravity is down). Now imagine you have resistance proportional to velocity (I.e linear resistance). If the object is moving up then velocity is negative and resistance is downwards which is positive. Similarly, if the object is moving down then velocity is positive and resistance is negative. Either way, the sign is always opposite. So the constant of proportionality is always negative so doesn’t change. So we can use the one equation F=mg-kv for both.

however, if the resistance was quadratic, then we have to use 2 equations because the sign of velocity squared stays the same, while the sign of resistance changes. So the constant of proportionality must change in sign. So we have to use 2 equations. Maybe there’s a cool way to use complex numbers or something to get around it (I’ll think about it),but the typical method is to just use 2 equations.

 

[carrotsss]

I haven’t done the paper yet but ive never learnt how to do it with one eqn of motion for vertical motion idk I’ve always learnt to do 2

just use 2?

 

[synthesisFR]

Ahh let me explain I promise within 30 seconds you’ll get it.

For the sake of discussion, let’s let downwards be positive and upwards be negative (you can reverse if you like but I prefer it this way cos gravity is down). Now imagine you have resistance proportional to velocity (I.e linear resistance). If the object is moving up then velocity is negative and resistance is downwards which is positive. Similarly, if the object is moving down then velocity is positive and resistance is negative. Either way, the sign is always opposite. So the constant of proportionality is always negative so doesn’t change. So we can use the one equation F=mg-kv for both.

however, if the resistance was quadratic, then we have to use 2 equations because the sign of velocity squared stays the same, while the sign of resistance changes. So the constant of proportionality must change in sign. So we have to use 2 equations. Maybe there’s a cool way to use complex numbers or something to get around it (I’ll think about it),but the typical method is to just use 2 equations.

Ah ok makes sense thanks man

Also why is life so unfair why do I have to compete with people like u

 

[Sam14113]

Ah ok makes sense thanks man

No worries

Also why is life so unfair why do I have to compete with people like u

I mean thank you but I just showed you a technique I in turn was shown by somebody else, and now that you know it I don’t think you’ve got any reason to think I’m ‘better’ than you

 

[scaryshark09]

Ok so hard complex number and sometimes proof questions are my weak point
so I either don’t want a hard complex number question, OR…, I want it to be super hard so no one gets it’s and I can accept getting 0 peacefully