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March 19, 2024, 08:05:03 pm

Author Topic: Mathematics Question Thread  (Read 1294190 times)  Share 

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jamonwindeyer

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Re: Mathematics Question Thread
« Reply #2460 on: August 13, 2017, 08:29:01 pm »
+3
To be honest, in the HSC that's either a method you just accept and take for granted, or don't use altogether. I didn't understand it until first year uni.

If you don't use it, the alternate approach is this, which is for granted:
1. Use simultaneous equations to find the point of intersection of the lines (call the point of intersection, say, P)
2. Find the gradient of the line between P and the other point, in your case being (2,4)
3. Use the point-gradient formula to find the equation of your required line.

Strongly advocate for this method over the k-method, it isn't that long and I don't think many schools teach the k-method anyway - Makes it easier on everyone ;D

beatroot

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Re: Mathematics Question Thread
« Reply #2461 on: August 15, 2017, 03:13:05 pm »
0
This isn't an actual Maths question, but a question regarding my rank and my marks in Maths. So I got back my mark back for my trial paper (I did the CSSA one) and I got 56% (lowest in a class of ten). My average for my internal mark is now 69%. Is there any hope for me left? Will I ever make it into the Band 5 range? If I get around 80-90% during the HSC, would I still make it into the Band 5 range. Last time I checked my ranking, it was 9 out 10. I feel like I'm dragging everyone down.
Which will hold greater rule over you? Your fear or your curiosity?

Please note that I am no longer active on the forums.
If you need any assistance, please message an admin or a natmod instead.

RuiAce

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Re: Mathematics Question Thread
« Reply #2462 on: August 15, 2017, 03:18:51 pm »
+5
This isn't an actual Maths question, but a question regarding my rank and my marks in Maths. So I got back my mark back for my trial paper (I did the CSSA one) and I got 56% (lowest in a class of ten). My average for my internal mark is now 69%. Is there any hope for me left? Will I ever make it into the Band 5 range? If I get around 80-90% during the HSC, would I still make it into the Band 5 range. Last time I checked my ranking, it was 9 out 10. I feel like I'm dragging everyone down.
Your performance in the final HSC exam always has the greatest impact on your final mark. How you perform in the final exam will determine whether or not you can enter the band 5 range.

This is all thanks to how moderation works (you can ask Jamon for the guide if you need it). At the end of the day, regardless of the actual marks you got in the internals, your final mark can go up depending on how you (AND ALSO you cohort) performs on the day.

Now that you've received your marks, you should now be focused on what you did do and did not do during the trial preparation block, and work to fixing all of these and improving for the finals. Despite your ranking, you're not gonna drag the cohort down provided you pull yourself up. It's now ALL about mark maximisation and using whatever resources you have to assist you.

If you fix it all up, you have no reason not to be able to get it.
« Last Edit: August 15, 2017, 08:29:39 pm by RuiAce »

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Re: Mathematics Question Thread
« Reply #2463 on: August 16, 2017, 08:49:26 am »
0
For the past HSC papers what years am I safe in doing? I'm just worried that doing some of the earlier ones might be too easy/too hard due to changes in the syllabus or the introduction of the reference sheet (not sure what year that was). Is it a good idea to skip some or should I start at 2001?

RuiAce

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Re: Mathematics Question Thread
« Reply #2464 on: August 16, 2017, 08:56:03 am »
+5
For the past HSC papers what years am I safe in doing? I'm just worried that doing some of the earlier ones might be too easy/too hard due to changes in the syllabus or the introduction of the reference sheet (not sure what year that was). Is it a good idea to skip some or should I start at 2001?
Papers that are too hard will only be papers that are prior to 2001. Anything from 2001 to 2016 inclusive is perfectly fine DESPITE the fact that 2016 was the first year they had the formula sheet.

Not more than 20% of the paper typically even requires the formula sheet (you should know the required formulas off by heart, everything else is just a bunch of methods). So there's no major problem at all.

In fact, you should push yourself to do all of them (unless of course, time constraints on other subjects) so that you can expose yourself to as much material and problem solving skills as possible.
« Last Edit: August 16, 2017, 09:00:13 am by RuiAce »

anotherworld2b

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Re: Mathematics Question Thread
« Reply #2465 on: August 18, 2017, 12:07:57 am »
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I am not quite sure what I did wrong for this question. Can I have help please?

RuiAce

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Re: Mathematics Question Thread
« Reply #2466 on: August 18, 2017, 12:14:26 am »
+3
I am not quite sure what I did wrong for this question. Can I have help please?
At the start, you wrote 0.5 as 5/100 instead of 5/10

12070

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Re: Mathematics Question Thread
« Reply #2467 on: August 18, 2017, 02:55:08 pm »
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Hey, I was just wondering how to find x find this information. It's nowhere near to scale as I don't have the actual question. The 9 in the middle is degrees by the way.

Thank you!

RuiAce

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Re: Mathematics Question Thread
« Reply #2468 on: August 18, 2017, 06:44:14 pm »
+2
Hey, I was just wondering how to find x find this information. It's nowhere near to scale as I don't have the actual question. The 9 in the middle is degrees by the way.

Thank you!
This question lacks information; with only the given information any (positive) value of x could work.

Whilst the upper triangle was uniquely defined, the lower was not.

12070

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Re: Mathematics Question Thread
« Reply #2469 on: August 18, 2017, 10:26:40 pm »
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This question lacks information; with only the given information any (positive) value of x could work.

Whilst the upper triangle was uniquely defined, the lower was not.

Sorry, I drew this on Microsoft Word as I don't have the question with me. The top triangle is meant to have one verticle side meaning the angle opposite x in the bottom triangle is 4.5. Also, the very bottom length of the bottom triangle is 100.

Edit: Just realised this question is incredibly easy with this information.
« Last Edit: August 18, 2017, 10:34:07 pm by 12070 »

good_stuff

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Re: Mathematics Question Thread
« Reply #2470 on: August 19, 2017, 11:19:06 pm »
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Hi all,
This isn't a specific math question but I'm confused about when to use quotient and product rules. There seem to be a lot more ways to solve equations in answer sections of the booklet including moving fractions out to the front of the swirly integrating sign (sorry I don't know what it's called :/) and changing the numberator's coefficient to the denominator's indice power...

Please help?
Thank you

RuiAce

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Re: Mathematics Question Thread
« Reply #2471 on: August 20, 2017, 12:51:51 am »
+2
Hi all,
This isn't a specific math question but I'm confused about when to use quotient and product rules. There seem to be a lot more ways to solve equations in answer sections of the booklet including moving fractions out to the front of the swirly integrating sign (sorry I don't know what it's called :/) and changing the numberator's coefficient to the denominator's indice power...

Please help?
Thank you
The fact that you've indicated the quotient and product rules (which are for derivatives), but also mention the word "solve" (which is used for equations) and the integral symbol (which is for integration, not differentiation) makes me cautious as to if you juggled the methods. We must not get differentiation and integration mixed up.

Please provided example questions.

(Also, for reference, that is called the integral symbol.)

anotherworld2b

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Re: Mathematics Question Thread
« Reply #2472 on: August 20, 2017, 12:59:44 am »
0
Can I have help with part d and e

jamonwindeyer

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Re: Mathematics Question Thread
« Reply #2473 on: August 20, 2017, 01:55:35 am »
+5
Can I have help with part d and e

For D, we know how likely it is a pilot can make it to 20 hours from part (b). We can do a similar calculation to find how likely it is they make it 15 hours. So you'd then be doing what is essentially a conditional probability calculation. I believe it would be as below, but I'm moving quickly, I await corrections if they are needed ;)



For E, you know the probability of totalling at least 20 hours before being shot down, from part (b). Use this in the binomial distribution with \(n=5\). So, if we let the number of pilots who satisfy the condition be the random variable \(Y\):



Where \(q\) is the probability you don't get 20 hours, and \(p\) is the probability that you do ;D

anotherworld2b

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Re: Mathematics Question Thread
« Reply #2474 on: August 20, 2017, 10:04:17 am »
0
Can I have help with this question too?