# Mathematics Extension 2 - 2016 Post-HSC Exam Thoughts (1 Viewer)

#### calamebe

##### Active Member
what do people think 87 would scale to?
Fairly high, maybe 95 or 96.

#### hiimesh

##### New Member
well if the cut off for e4 is high 60s as many seem to think, i believe an 87 would get you at least a 97, towards 98

#### hiimesh

##### New Member
would a 75-77 get me 94?

#### eating

##### Wannabe COMP god
well if the cut off for e4 is high 60s as many seem to think, i believe an 87 would get you at least a 97, towards 98
looking at rawmarks.info, it tends to be around 70.

#### hiimesh

##### New Member
indeed, im just observing since it was 70 in 2014, probably a little lower given the exam was harder

#### screwufan

##### New Member
this was so hard wtf yall think it was easy ? how lmao....im looking at about 55% raw what will this come back as a hsc mark as? i skipped almost all of 16 and 15
honestly i felt the same about it... i added up my potential marks and got around 40% raw. plus to make it worse my exam room was in the middle of a hallway of classrooms where people wouldnt be quiet despite all the 'hsc exams - please be quiet' signs and this yr 8 barged into my room during my exam. i don't understand why they didnt put me in the hall with the 2u people tbh.

i thought this paper was much harder than the couple past one's for me. also my teacher couldnt even teach me properly, i'd ask her a question and she'll go off on a tangent about something completely unrelated and for my internal exams i averaged an 85% which means the exams she set were too easy. i honestly did 4u to avoid 2u but now i realise it wasn't such a good idea. It also sucks that i was the only one in my school who did it, meaning what i get is what i get.

#### marxman

##### Member
I found it more challenging than recent years from 2013 onward. However I did not find it nearly as enjoyable as previous years where the exam was much more difficult either, all the results tended to be either redundant - 12 b (i for example, which redundantly made the question a 3-unit integration with hints, or just lazily set question such as Q14b) which would have been quite straightforward as a recurrence formula, yet, was made more challenging by increasing the level of tediousness.

The only real question i struggled with was 16a), which perhaps in my solution the working was slightly ambiguous. Unlike past years, there was no real level of logic required for anything apart from the first two parts of the derrangements question and perhaps the circle geometry question which could have been split into several parts. And even then, 16c) awarded essentially 3 free marks to anyone attempting the last 3 parts, as simple algebraic manipulation and a 3-unit level induction.

Overall whilst I am happy I believe I can get a high band 6 mark judging from online solutions, the inner maths nerd in me says this was a dry paper that really lacked anything interesting within it that left me slightly disappointed overall.

#### Katebate

##### Member
When you work your ass off for the past 1.5 years on 4u, doing heaps of past papers and having covered most exam style questions under the sun and averaging 90+ in most past papers. And then you go into the exam and nerves take over and you freeze.
1.5 years of working so that i can get 97+.
Now i'm not even sure i'll get an e4.
Same

#### hscc

##### Member
For the inequalities question, I just showed this, how many marks would it get? It doesn't prove for 0<x<1, only for x≥1. Maybe 1/3 or 2/3? :/

x^2≥1
x^2(x-1)≥(x-1)
x^3-x^2≥x-1
x^3-x^2+2x√x ≥ x-1+2x√x
x^3+1+2√x ≥ x^2 +x + 2x√x
(x√x +1)^2 ≥ (x+√x)^2
x√x+1 ≥ x+√x

#### InteGrand

##### Well-Known Member
For the inequalities question, I just showed this, how many marks would it get? It doesn't prove for 0<x<1, only for x≥1. Maybe 1/3 or 2/3? :/

x^2≥1
x^2(x-1)≥(x-1)
x^3-x^2≥x-1
x^3-x^2+2x√x ≥ x-1+2x√x
x^3+1+2√x ≥ x^2 +x + 2x√x
(x√x +1)^2 ≥ (x+√x)^2
x√x+1 ≥ x+√x
You'll probably get 1-2 marks (I think 1 because 2 seems too much, but not sure.)

$\bg_white \noindent You know, the result for 0 < x < 1 actually follows immediately from what you proved for x \geq 1. Since we showed \chi\sqrt{\chi}+ 1 \geq \chi +\sqrt{\chi} for all \chi \geq 1, the substitution x = \frac{1}{\chi} \iff \chi = \frac{1}{x} implies that \frac{1}{x}\sqrt{\frac{1}{x}} +1 \geq \frac{1}{x} + \sqrt{\frac{1}{x}} for all 0

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#### hscc

##### Member
You'll probably get 1-2 marks (I think 1 because 2 seems too much, but not sure.)

$\bg_white \noindent You know, the result for 0 < x < 1 actually follows immediately from what you proved for x \geq 1. Since we showed \chi\sqrt{\chi}+ 1 \geq \chi +\sqrt{\chi} for all \chi \geq 1, the substitution x = \frac{1}{\chi} \iff \chi = \frac{1}{x} implies that \frac{1}{x}\sqrt{\frac{1}{x}} +1 \geq \frac{1}{x} + \sqrt{\frac{1}{x}} for all 0
Ohhh....that makes so much sense now, thanks!

#### hscc

##### Member
I did some stupid shit, so I'm trying to pinpoint some partial marks lol.

#### InteGrand

##### Well-Known Member
I did some stupid shit, so I'm trying to pinpoint some partial marks lol.
$\bg_white \noindent Did you say clearly in your working that you were only proving it for x \geq 1?$

#### hscc

##### Member
$\bg_white \noindent Did you say clearly in your working that you were only proving it for x \geq 1?$
I initiated my working like this:

Consider x≥1 (as we are given x≥0)
(followed by the working I showed you above)

It's rather badly worded, as it seems like I'm getting the fact x≥1 as we are given x≥0 which virtually makes no sense......But I hope they overlook that somehow. Or perhaps interpret the statement as "This guy is proving true for x≥1 because at least he knows x≥0." But I think I ended my proof stating that it's also true for x≥0, as that's what the question demanded - and I deemed it to be because x≥0 is the domain of √x.

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#### InteGrand

##### Well-Known Member
I initiated my working like this:

Consider x≥1 (as we are given x≥0)
(followed by the working I showed you above)

It's rather badly worded, as it seems like I'm getting the fact x≥1 as we are given x≥0 which virtually makes no sense......But I hope they overlook that somehow. Or perhaps interpret the statement as "This guy is proving true for x≥1 because at least he knows x≥0."
Basically your best hope is to hope the markers assumed you were trying to prove it only for x >= 1 and that they'll give some marks for that (because that's what you actually did, mathematically speaking.).

#### hscc

##### Member
Basically your best hope is to hope the markers assumed you were trying to prove it only for x >= 1 and that they'll give some marks for that (because that's what you actually did, mathematically speaking.).
Well I hope they give me benefit of the doubt. I hope it's not naive to consider that 1 mark is already guaranteed - and that this is a dilemma between 1 or 2 marks.

#### InteGrand

##### Well-Known Member
Well I hope they give me benefit of the doubt. I hope it's not naive to consider that 1 mark is already guaranteed - and that this is a dilemma between 1 or 2 marks.
I'm not sure but that might depend on whether you tried to claim you'd proved it for all x ≥ 0 (that's why I asked if you'd made it clear you weren't).

#### Halp00

##### New Member
Hey does anyone know whether the machines pick up pencils?

I used a pencil to draw the graphs, and not pen

#### Flatchakra

##### New Member
What do you guys think is the lowest raw mark or hsc mark required for a state rank?

#### hscc

##### Member
What do you guys think is the lowest raw mark or hsc mark required for a state rank?
Perhaps 95 or 96 raw.