Maths Extension 2 Thoughts and Feelings (1 Viewer)

[notme123]

Do the HSC markers base your marks off of your

Considering the test was pretty hard, it will most likely be scaled to a solid 90 to 95+

no they would defs be in 97+ range. 85 went to 95 last year and people said that was 'easier'

 

[Zyzz_139]

Damn, so that would that mean 75 to 80, would be scaled to 90 to 95?

no they would defs be in 97+ range. 85 went to 95 last year and people said that was 'easier'

 

[Zyzz_139]

no they would defs be in 97+ range. 85 went to 95 last year and people said that was 'easier'

Also thanks for the correction!

 

[notme123]

Damn, so that would that mean 75 to 80, would be scaled to 90 to 95?

ye i think a 77 went to 93 if I'm not mistaken.

Mathematics Extension 2 – HSC Raw Marks Database

rawmarks.info

check this

 

[MemeCognoscente]

ye i think a 77 went to 93 if I'm not mistaken.

Mathematics Extension 2 – HSC Raw Marks Database

rawmarks.info

check this

damn a 65 went to 88 last year, does that mean E4 cutoff for this year could be around there?

 

[Vall]

damn a 65 went to 88 last year, does that mean E4 cutoff for this year could be around there?

maybe dont get your hopes up too high just yet tho. I feel like every year all the year 12s online complain about how much harder the exams were.

 

[yanujw]

BOS has defeated SMH.

The errors spoken about previously here on BOS have embarrassed them enough to remove the video.

If you click on the link now you get

View attachment 36703

Wasn't that the usual video they get some poor hs student to go through (this year it was Prairiewood HS I think). Jeez... that's embarassing for that person.

Looks like now they've now gone straight to a JR student for the (correct) answer.

The hardest 2022 Maths Extension 2 exam question explained

Watch James Ruse Agricultural High School student Prithika Dhiwaharan solve one of the hardest Mathematics Extension 2 exam questions.

www.smh.com.au

 

[idkkdi]

literally 1984. they need to be held accountable for their actions for not being able to do such a routine and easy question ugh. (sarcasm if anyone didn't pick it up)

also how do they decide whats the hardest question?

clearly by looking at which question has the most algebra bashing lmao

 

[notme123]

There is a new article on it at https://www.smh.com.au/national/nsw...-hsc-maths-questions-yet-20221021-p5brpl.html but they didn’t acknowledge their old video had to be replaced.

Seems like they are just trying to save face.

idk why smh articles make me cringe a little inside. especially when they get quotes from people but paraphrase it wrongly 'questions about projections that asked students to analyse the components of a motion of a particle could be read as “ambiguous.” ' I don't get what this is saying. There were no projections, only projectile motion. ik journalists arent mathematicians but including technical words for the sake of it doesn't do anything for the article or the readers.

 

[notme123]

clearly by looking at which question has the most algebra bashing lmao

last years algebra bashing was way worse. this year you literally just had to integrate twice and you're done. not denying the difficulty but the mathematical component wasn't very demanding

 

[Allan Mekisic]

The James Ruse answer to Q 16 b I think is incorrect. The solution did not take into account that there are two equations of motion. One for the journey upwards where a = - g - 0.1v and for the journey downwards a = g - 0.1v.

 

[youssseeefffff-wahbbbaaa]

Hey guys, here is my solution to the very last question of the ext 2 hsc 2022. Though i wasnt able to fully complete it during the exam cuz it was too time pressured at least i came up with my own solution. Please correct me if theres any error. Good luck to everyone!

 

[idkkdi]

last years algebra bashing was way worse. this year you literally just had to integrate twice and you're done. not denying the difficulty but the mathematical component wasn't very demanding

compared to the rest of q16 parts this yr, it had a bit more algebra.

q16d should have been the favourite for the hardest q this yr. required a bit of creativity, while q16b looks like it came out of terry lee lmao.

 

[Daedalus13]

The James Ruse answer to Q 16 b I think is incorrect. The solution did not take into account that there are two equations of motion. One for the journey upwards where a = - g - 0.1v and for the journey downwards a = g - 0.1v.

This is what I thought in the exam (to my demise as I made some algebraic errors), but I think the change in sign of the velocity accounts for this change in direction. You end up with the same answer nonetheless (if you don't screw up like I did).

 

[okkk]

Well that's much better.

I've attached a screenshot again

View attachment 36704

I'm still confused by this solution lmao does anyone know how she's allowed to just use the upwards equation the whole way through and sub in x=0, seems to contradict everything I've learnt in mechanics

 

[notme123]

I'm still confused by this solution lmao does anyone know how she's allowed to just use the upwards equation the whole way through and sub in x=0, seems to contradict everything I've learnt in mechanics

Thats why i said that question felt illegal in one of my posts but this post below is the reason why.

I think the change in sign of the velocity accounts for this change in direction.

16 b and d are questions i feel people would get if they've seen similar versions or were taught those very specific details. can someone please prove I'm not crazy in saying I've seen 16 d somewhere before

 

[okkk]

compared to the rest of q16 parts this yr, it had a bit more algebra.

q16d should have been the favourite for the hardest q this yr. required a bit of creativity, while q16b looks like it came out of terry lee lmao.

Tbh the polynomial thing for 16d wasn't that necessary. Once you have that they're all magnitude 1, you can use z_1+z_2+z_3=1 to draw a rhombus (since their lengths are the same) and deduce one of them has to be 1 and the other two are of the form e^(itheta) and -e(itheta), then you can use the multiplying identity to get theta is pi/2, I think this is probably the most intuitive way cos I got up to that question with two minutes left cos I'd blown it all on the mechanics one

 

[Trebla]

I'm still confused by this solution lmao does anyone know how she's allowed to just use the upwards equation the whole way through and sub in x=0, seems to contradict everything I've learnt in mechanics

This is because v is defined as velocity in the solution (with upwards defined as positive) instead of speed (which is what most people do). When you define v as speed then you tend to define the direction of motion as positive. This usually makes adding/subtracting the vectors more intuitive as you can define the signs yourself using the magnitudes given - i.e. you don’t need to think about the sign of v.

Once you define v as velocity (which is a vector quantity), you have to take a bit more care on the signs because the vector can change direction.

Technically speaking though the question defined v as speed…

 

[idkkdi]

Tbh the polynomial thing for 16d wasn't that necessary. Once you have that they're all magnitude 1, you can use z_1+z_2+z_3=1 to draw a rhombus (since their lengths are the same) and deduce one of them has to be 1 and the other two are of the form e^(itheta) and -e(itheta), then you can use the multiplying identity to get theta is pi/2, I think this is probably the most intuitive way cos I got up to that question with two minutes left cos I'd blown it all on the mechanics one

nah you can't make that deduction that 'one of them has to be 1'.

 

[okkk]

nah you can't make that deduction that 'one of them has to be 1'.

It's impossible to construct unit vectors that add together to get one if one of the is not one. For example, construct the first one anywhere you want, then consider the second vector as one, if it shifts up or down, the distance between its tip and 1 would change and it no longer 1, so the third vector cannot get to one if the second vector is not 1. I think at least, I can't visualise a counter example