Mathematics Predictions/Thoughts (1 Viewer)

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For question 15, I used similar triangles rather than Pythogoras' Therom. Idk why I thought it was a similar triangle question. Anyway, I still got the same answer. Attached is my working. Can anyone verify whether it's correct and would warrant 3/3?
 

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StudyOnly

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For question 15, I used similar triangles rather than Pythogoras' Therom. Idk why I thought it was a similar triangle question. Anyway, I still got the same answer. Attached is my working. Can anyone verify whether it's correct and would warrant 3/3?
Why would it not give you 3/3?
If all your working was there and it was correct, then they would give you 3/3. There are multiple ways of doing basically all questions. You'll be fine as long as you wrote everything needed.

I also used similar triangles btw, but I just proved triangle ACD is similar to triangle CBD straight up, so was less working.
 

Makeanote

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Your working / reasoning seems to be correct. I would imagine this would receive full marks. If you follow an imagined criteria for this question - Establishes similarity of triangles (1), implements properties of similar triangles (ie. relates sides in similar triangles) (2) and simplifies ratios to correctly present the required relationship (3).
Trust this helps.
Ian
 
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Your working / reasoning seems to be correct. I would imagine this would receive full marks. If you follow an imagined criteria for this question - Establishes similarity of triangles (1), implements properties of similar triangles (ie. relates sides in similar triangles) (2) and simplifies ratios to correctly present the required relationship (3).
Trust this helps.
Ian
Great, thanks!
 
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Why would it not give you 3/3?
If all your working was there and it was correct, then they would give you 3/3. There are multiple ways of doing basically all questions. You'll be fine as long as you wrote everything needed.

I also used similar triangles btw, but I just proved triangle ACD is similar to triangle CBD straight up, so was less working.
Okay, that's good to hear. Thanks!
 

Stuffyman7

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Last question wasn't the hardest question in my opinion, for which I got r=root 2 +1, i could see how the financial series question could have stumped a lot of students in terms of the number of terms in the geometric series you obtain, overall a fairly less than average paper on the difficulty, hopefully i can achieve a state ranking
 

fet

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sad story:
my stupid ass was going for a perfect score, but for that common difference question in Q12 (WHY), I kept getting 3 instead of 1/3. I did the question like 4 times over two booklets and I kept writing 3/9 is equal to 3 instead of 1/3, I knew smth was sO OFF but I didn't end up realising what it was.
the one time I use my brain instead of a calculator for a 6 year old's math equation, I mess up.
-- sincere thanks for your pity
 

jskeza

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sad story:
my stupid ass was going for a perfect score, but for that common difference question in Q12 (WHY), I kept getting 3 instead of 1/3. I did the question like 4 times over two booklets and I kept writing 3/9 is equal to 3 instead of 1/3, I knew smth was sO OFF but I didn't end up realising what it was.
the one time I use my brain instead of a calculator for a 6 year old's math equation, I mess up.
-- sincere thanks for your pity
At least you'll get 98-99 depending on amount of marks, which is really good
 
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Stuffyman7

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And there goes my hopes of a state ranking, i got 99/100 because i didnt write 1.05 or whatever it was in the denominator to the power of 4 but did for everything else. In fact my answer was ended up being correct for all decimal places except 1, lol what a fail
 
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And there goes my hopes of a state ranking, i got 99/100 because i didnt write 1.05 or whatever it was in the denominator to the power of 4 but did for everything else. In fact my answer was ended up being correct for all decimal places except 1, lol what a fail
Was your final answer 24 years? You might be able to still score the 3/3
 
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For 15cii, did you all just substitue x = 2 into the derivative to show that it's a minimum? I solved the equation, got x = -8 and x = 2, then discarded x = -8 (since x is length), and then used the Derivative table to show there's a minimum at x = 2. Do you guys reckon NESA would be expecting to see the -8 too?
 

jskeza

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For 15cii, did you all just substitue x = 2 into the derivative to show that it's a minimum? I solved the equation, got x = -8 and x = 2, then discarded x = -8 (since x is length), and then used the Derivative table to show there's a minimum at x = 2. Do you guys reckon NESA would be expecting to see the -8 too?
It does say show x=2 is a minimum which you did, so I think you will be fine.
But just let it go now mate, the exam is over. We can't change it anymore just wait for results and go study for your next exam
 

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What would a raw mark of 87 scale to for this exam?
 

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