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Maths Ext 2 Predictions/Thoughts (1 Viewer)

tywebb

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Just finished watching the video. My only criticism is at the very end he used a because symbol whereas he should have used a therefore symbol
 

notme123

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Just finished watching the video. My only criticism is at the very end he used a because symbol whereas he should have used a therefore symbol
unwatchable. this kid shouldn't even be doing maths let alone 4u. jk jk but thats such a simple mistake how can you screw that up thats worse than my mistake.
 

Siwel

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unwatchable. this kid shouldn't even be doing maths let alone 4u. jk jk but thats such a simple mistake how can you screw that up thats worse than my mistake.
yeah i would say messing up algebra is underappreciated marks wise so maybe i get 5, i did have the intent to get the right answer
 

notme123

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yeah i would say messing up algebra is underappreciated marks wise so maybe i get 5, i did have the intent to get the right answer
exactly, might as well give me a sr at this point.
 

Siwel

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exactly, might as well give me a sr at this point.
ngl for the weird circle and ln function volumes i somehow made up my own way to find the volumes rotated and got the right solution
 

Paradoxica

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Matrix solutions: https://www.matrix.edu.au/2021-hsc-maths-ext-2-exam-paper-solutions/

Other sites to keep an eye on are

https://www.itute.com/download-free-vce-maths-resources/free-maths-exams/

and

http://advancedmathematics.com.au (Terry Lee)

Historically Terry Lee used to be the first with solutions up.

Recently he has been beaten by a few others.

Itute are very slow to put them up - maybe a month or so - some say they take a wiser approach than rushing to be the first.

Itute also seem to be consistently the most complete too - even putting them up for Standard 1 - which is very rare.
Matrix didn't put a dashed line for the straight line segment joining z=0 to z=-π. -1 mark.
 

notme123

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ngl for the weird circle and ln function volumes i somehow made up my own way to find the volumes rotated and got the right solution
i didnt even realise you could do have a cube - a hemisphere i did a full integral hahaha
 

tywebb

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unwatchable. this kid shouldn't even be doing maths let alone 4u. jk jk but thats such a simple mistake how can you screw that up thats worse than my mistake.
My criticism stands.

But I want to downplay it. It's not a great drama.

He went through quite a bit of hefty algebra and I'm glad he was the one doing it, not me.

Overall I think he did a great job.
 

notme123

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My criticism stands.

But I want to downplay it. It's not a great drama.

He went through quite a bit of hefty algebra and I'm glad he was the one doing it, not me.

Overall I think he did a great job.
how does one even get chosen to do this.
1. go to a prestigious school which will pay the smh to do this article
2. become ranked first in x2
3. profit
 

Siwel

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how does one even get chosen to do this.
1. go to a prestigious school which will pay the smh to do this article
2. become ranked first in x2
3. profit
on the facebook 2 days before they asked ppl, are you 1st in your school for x2?
 

5uckerberg

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ah yes the classic article where boomers question why we still do things like this because it has no value to society. a pattern ive noticed is that top schools always get the opp to do this.
You took the words right out of my mouth.
 

s97127

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1637231783888.png
For this question, i want to prove 5^n -2^n - 3^n > 0 for n>= 2

(2+3)^n - 2^n - 3^n = 2^(n-1).3 + 2^(n-2).3^2 +....+ 3^(n-1) > 0 (QED)

Is this proof correct?
 

Trebla

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View attachment 33882
For this question, i want to prove 5^n -2^n - 3^n > 0 for n>= 2

(2+3)^n - 2^n - 3^n = 2^(n-1).3 + 2^(n-2).3^2 +....+ 3^(n-1) > 0 (QED)

Is this proof correct?
Almost...except you forgot the binomial coefficients.

Also, generally speaking, proving something is positive to prove it is non-zero doesn’t always work (it works in this case though). You can have expressions that can be positive or negative but is non-zero.
 

Eagle Mum

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Correct I got 100 for x1 but i got nowhere close to a state rank.
I imagine that by scaling extension students up, it’s quite compacted at the top, so amongst the cohort with a scaled mark of 100 would be a range of raw marks, but anyone who achieves a raw mark of 100 deserves to be equal first. Students in different schools who achieve a perfect score in the exam shouldn’t be ranked based on school assessments, since assessments aren’t standardised. Congratulations on your awesome achievement!
 

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