Discussion and Suggested Solutions - Mathematics 2017

[avalansh7]

So was the answer for 16c) 0<a<4, where a=2 as well (r=0)? Praying for 100 Also ty for the person who replied for the domain question. i got that answer.

[bimberfairy]

Hey,
I just sat the exam today and got pretty much the same answers. I really hope 11h was only asking for domain and that financial was a bit tricky though i got it in the end. My classmates are questioning Q16c for the limiting sum=2 question. Most of us got 0<a<4, but since it is a GP half of us are questioning whether r=0 is possible and hence a=2 is a solution within this range. So could it perhaps be 0<a<4, a is not equal to 2, or is it just 0<a<4. I put 0<a<4.

If the domain question you're referring to was the one with x in the square root, then yes, i'm very sure it was asking for domain only!

[jamonwindeyer]

tbh for that area under the curve question, i got k = -2.5
anyone else?

What was your method? I may have screwed up

Is it fine is I used transversals as my reasoning for that isosceles proving question....BM/MC = BD/DE....then i did the arranging of the equestion they gave and the one I made which was i think same as urs....

I think that sounds alright!

Anyone have any guesses for the raw marks for band allocations this year? For band 5?

I reckon they'll be semi-low this year. 2013's B6 cutoff was about 77, I reckon this could be similar, maybe even 75 or so. B5 cut-off maybe very low 70's?

If we did the questions out of order would that affect our marks in anyway? For example for the cycling question I did part ii in my extra writing book and not before part iii

Provided they can find everything you'll be fine

Hey mate,

re your solution regarding question 16 aii, in which you needed to find x, I found it easier to prove similarity of triangles ace and the other one (equiangular if sina=sinb), then just use ration of sides to find x. came out as 5/7=x/9-x and then solve. less opportunity for calculator mis-entry for the quad formula.

Definitely a way better method my friend!! Brute force was pretty ugly hey

The question about the three isosceles triangles (15A) the common answer is 36deg but did anyone else also get 108deg as an answer for obtuse-angled triangles? I am fairly sure there are two answers but curious what the general consensus on this is and if NESA is likely to recognise both answers.

I don't think that could be possible since you need to fit three of the angles, plus an extra, into 180 degrees for them to be parallel right? Could you perhaps elaborate further?

for the kangaroo question, i got 870 because i used the unrounded answer of k . i gave the final answer in 2sf. do you think i will still get the mark?

I reckon you should!

what do you guys think the raw mark for state rank would be for this test?

Still 99 or 100 I think

If the domain question you're referring to was the one with x in the square root, then yes, i'm very sure it was asking for domain only!

Confirming it was - I've only just realised I added the work for myself!

[amberberrie]

Raw mark for band 6??

[alihkhan8]

So I got 83/100 for this exam. My school rank is 11/190 and last year around 50 people at my school got band 6.
Any chance of me getting a band 6 or have I fked it?

[liya1234]

thank you so much for getting these up for us!!! i really appreciate it xx

[jamonwindeyer]

Raw mark for band 6??

High 70's I reckon is a safe bet, it could be as low as like 75 at a stretch

So I got 83/100 for this exam. My school rank is 11/190 and last year around 50 people at my school got band 6.
Any chance of me getting a band 6 or have I fked it?

Pretty likely you'll get a B6 I'd wager my friend - Congrats on a great score in a tough exam

thank you so much for getting these up for us!!! i really appreciate it xx

Very welcome! I enjoy doing the exams every year, keeps me on my toes - I don't really like lecturing a subject I haven't sat the exam for in recent memory

[Atargod123]

For the t(2/3) question. Make t =m quadratic equation question.            -27 to the power of 2/3 gives error on calculator why?

[liya1234]

also just a question - for 16b) i did the first part equating the infinite sum to 2 and rearranged but got stuck there and did not relate it to the correct property where absolute value of r is less than one - would I still be able to get a mark for that?

[.Woke.]

Hey guys, asking for a friend, what would a raw mark of 90+ be in this exam?

[avalansh7]

I thought it was actually a well-designed paper. I was looking at Q16 c for like 10 minutes, completely blank and then tried similar triangles and it worked out. Some of the questions made you work hard for the marks and it felt so good working them out

Can't disagree with that.

[jamonwindeyer]

For the t(2/3) question. Make t =m quadratic equation question.            -27 to the power of 2/3 gives error on calculator why?

Just because of the order probably, but it is calculable - Try applying the power of two first (squaring) and then cube root it

also just a question - for 16b) i did the first part equating the infinite sum to 2 and rearranged but got stuck there and did not relate it to the correct property where absolute value of r is less than one - would I still be able to get a mark for that?

Yep I reckon you would

Hey guys, asking for a friend, what would a raw mark of 90+ be in this exam?

Raw 90ish would align to mid-high 90's I reckon

[Harry_Damon]

What does everyone think the raw Mark cut off will be for a band four?

[jamonwindeyer]

What does everyone think the raw Mark cut off will be for a band four?

I reckon low to mid 60's as a super super super rough guess

[Anfar3]

Hey Jamon,

Just wondering how accurate ur predictions for raw mark cutofffs for b6s are? How successful have u been in prev yrs? Just dont wanna get my hopes up too high lol.

Thanks