Question 14 Solutions (1 Viewer)

Carrotsticks

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I'll just release them as I do them. Won't be as fast or nice as 4U guys, not at home =(

BTW Projectile motion can be done a lot faster if you practise enough with trig inequalities, but I included a diagram for reference.













 
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YoYoWayne

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Thanks heaps for the solution!
I wonder if I left my 75 degrees in radians to 2 d.p. will I be penalised?
 

Carrotsticks

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As long as everything else is in radians, it will be fine.
 

Carrotsticks

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Not going to bother with the last part, the solution is just plain messy and IMO this paper doesn't do 3U any justice.

Very disappointing, Board of Studies.

If you want me to do specific questions, just let me know and I'll do them.
 

nucgaek

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Do you happen to have a copy of the paper you could put up?
 

Kieran95

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Not going to bother with the last part, the solution is just plain messy and IMO this paper doesn't do 3U any justice.

Very disappointing, Board of Studies.

If you want me to do specific questions, just let me know and I'll do them.
You think the paper was too easy?

And thanks for the solutions!
 

Carrotsticks

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Unfortunately they are not allowed to be distributed here anymore.
 

mike12345678

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Not going to bother with the last part, the solution is just plain messy and IMO this paper doesn't do 3U any justice.

Very disappointing, Board of Studies.

If you want me to do specific questions, just let me know and I'll do them.
what was wrong with the paper , carrot?

too easy/ hard or just plain stupid?
 

Sanjeet

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Q14 b iii) when you say 250sin^2x >= 150, the next line is sin^2x>=1/2. 150/250 is not 1/2...at least i don't think so o_O
 

Carrotsticks

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what was wrong with the paper , carrot?

too easy/ hard or just plain stupid?
1. Too easy. No real proofs, just tedious calculations.

2. Too heavily inclined towards 4U students (the curve sketching one and the circle geometry in Q14)

3. Projectile motion wasn't even a proper projectile motion problem. Most of the work was just solving trig equations.

4. Very last rates of change is just like any other one, and the end result is just some random answer. Usually, it's a nice result.

5. No binomial identities? Seriously?

Copyright issues, which I think is just silly TBH for a few reasons.

1. They will be uploaded anyway.

2. How can you even copyright Maths questions and proofs?
 

Carrotsticks

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Q14 b iii) when you say 250sin^2x >= 150, the next line is sin^2x>=1/2. 150/250 is not 1/2...at least i don't think so o_O
Haha, thanks for pointing that out. 150/250 is most certainly not equal to half. Doesn't change the answer though, the bounds are the same because the domain acquired from x lies within the domain acquired from y (with the correct calculation this time =p)

One of my stronger fails since I thought that $50 is not enough for a $45 dollar book.
 

mike12345678

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1. Too easy. No real proofs, just tedious calculations.

2. Too heavily inclined towards 4U students (the curve sketching one and the circle geometry in Q14)

3. Projectile motion wasn't even a proper projectile motion problem. Most of the work was just solving trig equations.

4. Very last rates of change is just like any other one, and the end result is just some random answer. Usually, it's a nice result.

5. No binomial identities? Seriously?



Copyright issues, which I think is just silly TBH for a few reasons.

1. They will be uploaded anyway.

2. How can you even copyright Maths questions and proofs?

haha so true. what do you think the cut will be for am e4?

and also that is so stupid. since when was hsc papers copyrighted???
 

lolcakes52

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I totally agree with carrot. The paper was nothing extraordinary. Following extension 2, this was a cake walk. I finished maybe 30 minutes early and made a silly mistake in the very last question where I forgot to add the one. Super simple paper.
 

mike12345678

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I totally agree with carrot. The paper was nothing extraordinary. Following extension 2, this was a cake walk. I finished maybe 30 minutes early and made a silly mistake in the very last question where I forgot to add the one. Super simple paper.
maybe for you 4uniters it was easy. but for decent 2/3unit students it was a little challenging for example the last trig question and like carrot said the sketching question and the circle geo questions. i got both the last two but im estimating a mark between 50-56/70 so it definitely wasnt easy
 

NBGHHS

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Terry lee solutions are out as well...but it's pretty confusing. I like carrotstick's working out :p
 

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