# Carrotsticks' Solutions 2015 Extension 1 HSC (1 Viewer)

#### suwag

##### New Member
hi, what do you think a 68/70 would align to?

#### SNT k

##### New Member
also for question 12 d iii shouludnt the answer be 2.56 thats what i got? did i do something wrong?

#### ENFP

##### New Member
That's strange. I didn't edit it back, so not sure why it decided to do that.

Anyway, I'll fix it now, cheers for pointing that out.
That also seems to have happened with 13bi

#### SNT k

##### New Member
for question 13b i should it have the 18C2 as well cos its part of the binomiinal expansion??

#### InteGrand

##### Well-Known Member
Tell me that story please xD
Also this is gonna come across as hella arrogant, but say in hypothetical dreamland I get state ranks in Physics, Software and 4U Maths, would I then be able to get 99.95 with a mid/low end E4 in 3U Maths?
Yes, depends on English.

#### IamKirby

##### Member
For the circle geometry, part i and ii, since they ask 'What is the size of the angle...?', were reasons needed? If so, another 2 marks lost. Especially because I didn't read that we needed to copy the diagram.

#### Carrotsticks

##### Retired
That also seems to have happened with 13bi
for question 13b i should it have the 18C2 as well cos its part of the binomiinal expansion??
I am out atm so I cannot fix it now, but cheers for pointing it out. Very unusual for the solutions to have reverted itself like that for no reason.
For the circle geometry, part i and ii, since they ask 'What is the size of the angle...?', were reasons needed? If so, another 2 marks lost. Especially because I didn't read that we needed to copy the diagram.
I do not remember the mark allocations, the answer depends on that.

#### IamKirby

##### Member
I am out atm so I cannot fix it now, but cheers for pointing it out. Very unusual for the solutions to have reverted itself like that for no reason.

I do not remember the mark allocations, the answer depends on that.
They were both worth 1 mark each, part iii which specified 'give reasons' was worth 2

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#### InteGrand

##### Well-Known Member
Hey carrot, other than mathtype, are there any other programs that write up math equations?
LaTeX of course!

#### Ekman

##### Well-Known Member
LaTeX of course!
Is LaTeX a downloadable program that I can use to write up pdf's containing math equations? I thought LaTeX was a specific code used.

#### Zen2613

##### Member
That's a very short mountain then.

It's too late now for you, but for this reason I always tell my students to verify their answer with what makes sense in real life. Is your answer reasonable? If not, double check it.

So if I got a 62m high mountain, I'd immediately be suspicious.
Lol i got 20 meters

#### InteGrand

##### Well-Known Member
Is LaTeX a downloadable program that I can use to write up pdf's containing math equations? I thought LaTeX was a specific code used.
Nope lol (to the last sentence), you can download it and write up documents containing equations. Depending on your Operating System, there's different places to get it from. They're listed here: https://latex-project.org/ftp.html

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#### Carrotsticks

##### Retired
I am back, and just reverted the file to how it was before!

#### helloimyellow

##### Active Member
Hi, for question 14a)ii), I first proved that the particle was moving downwards at time t = 2v/g.sqrt(3) (I know that it's part iii) but I proved it anyway :S).

Then, I said alpha = arctan(-y dot/x dot), since the particle was moving downwards, and ended up with alpha = pi/3.

Would I get deducted one mark for not using alpha = arctan(y dot/x dot)? Thanks in advance!!

#### Carrotsticks

##### Retired
Hi, for question 14a)ii), I first proved that the particle was moving downwards at time t = 2v/g.sqrt(3) (I know that it's part iii) but I proved it anyway :S).

Then, I said alpha = arctan(-y dot/x dot), since the particle was moving downwards, and ended up with alpha = pi/3.

Would I get deducted one mark for not using alpha = arctan(y dot/x dot)? Thanks in advance!!
This is a tough one, I am not completely sure whether you would be awarded full marks or not for this response.

#### ENFP

##### New Member
In question 5, why is the answer A rather than C? A point exists when y=0 but not when y=3....

#### Carrotsticks

##### Retired
In question 5, why is the answer A rather than C? A point exists when y=0 but not when y=3....
A curve can cross a horizontal asymptote. Remember, the horizontal asymptote is the behaviour of the curve EVENTUALLY. It's not like a vertical asymptote that absolutely cannot be crossed for normal functions.

Besides, the fact that the degree of the denominator > degree numerator is enough to suggest that y=0 is a horizontal asymptote.

The only way that y=k , where k=/=0, is a horizontal asymptote in rational functions, is when deg (numerator) = deg (denominator).