VCE Specialist 3/4 Question Thread!

[lzxnl]

lol serves me right for doing my exam 1s in chunks rather than like one per day. my mistake

and I'm here for you always

@nliu, Euler's formula isn't in spesh is it? At least I don't remember seeing it in the essential textbook anywhere

It's not, but you could easily prove it to spesh students.
Or, if you want, differentiate e^-ix*(cos x + i sin x) treating i as a constant and you should get zero. Subbing in x=0, you see that this expression must then be identically equal to 1. e^-ix=1/e^ix=>cis x/e^ix=1 => cis x = e^ix

[sin0001]

Q15 of the 2004 VCAA Exam still in the current study design? Or not anymore? (http://www.vcaa.vic.edu.au/Documents/exams/mathematics/2004specmaths1.pdf)

[brightsky]

yes I think so. there are a whole bunch of silly approximation methods that you need to know. you don't really need to learn anything new; you just need to know what they mean when they use jargon like 'midpoint rule' and 'trapezoidal rule'.

[sin0001]

yes I think so. there are a whole bunch of silly approximation methods that you need to know. you don't really need to learn anything new; you just need to know what they mean when they use jargon like 'midpoint rule' and 'trapezoidal rule'.

Gotta be kidding me :S
I don't recall coming across these questions in essentials, any idea where I can learn what each method consists of?

[lzxnl]

yes I think so. there are a whole bunch of silly approximation methods that you need to know. you don't really need to learn anything new; you just need to know what they mean when they use jargon like 'midpoint rule' and 'trapezoidal rule'.

In all of the VCAA exam questions I've done since 2006, I haven't come across those integral approximation rules. You don't need them.

[sin0001]

Had a query regarding question 2e) of VCAA 2004 (exam 2):
http://www.vcaa.vic.edu.au/Documents/exams/mathematics/04specialistmaths2.pdf
-I made the x-coordinate equal to 1 and then found the possible times at which this was the case (5pi/4 & 25pi/4)
-I subbed in both those time values into the j component to show that y coordinate didn't equal 33, and hence ball never collided with J
Would there be a mark taken off for using t=5pi/4, because according to the examiner's report, t=25pi/4 was the only time relevant

Someone please tell me this is the hardest VCAA maths exam ever :S

[BubbleWrapMan]

Had a query regarding question 2e) of VCAA 2004 (exam 2):
http://www.vcaa.vic.edu.au/Documents/exams/mathematics/04specialistmaths2.pdf
-I made the x-coordinate equal to 1 and then found the possible times at which this was the case (5pi/4 & 25pi/4)
-I subbed in both those time values into the j component to show that y coordinate didn't equal 33, and hence ball never collided with J
Would there be a mark taken off for using t=5pi/4, because according to the examiner's report, t=25pi/4 was the only time relevant

Someone please tell me this is the hardest VCAA maths exam ever :S

I don't think you would get a mark taken off for that.

[aestheticatar]

Help needed! Thanks heaps!!!

[aestheticatar]

Is the area formula for segment of circle assumed knowledge for our exam? Not too sure if it's
included in the study design. If so, what other unexpected areas can they ask us, that is not included in the formula sheet?

E.g. Solutions for question attached included the formula of segment I think?

Thankz heapz

[Phy124]

Help needed! Thanks heaps!!!

Firstly I'll work out the velocity 0.4 second before it hits the ground in terms of by using this time value:







Now I'll work out the velocity at this same point in terms of and , from a starting point where its velocity is zero:

(*Note: the v in this equation is the same as the u in the last)



Therefore we know that;



Rearranging will yield

[thecreeker]

Some help please
I don't understand how they do this in the solutions

[brightsky]

extend the line AB until it hits the x-axis (call this point C). you know angle OBA is 60 degrees since equilateral triangle. so angle OBC is 180 - 60 = 120. so angle OCB is 180-a-120 = 60-a.
now do the number crunching.
m2 = tan(180 - (60-a)) = -tan(60-a)
using compound angle formula and what not
m2 = -(tan(60) - tan(a))/(1+tan(60)tan(a))
= -(sqrt(3)-tan(a))/(1+sqrt(3)tan(a))
= (tan(a)-sqrt(3))/(1+sqrt(3)tan(a)) as req

[thecreeker]

thanks man
that was fairly basic but I never think of extending lines in an exam situation and dig myself a hole

[sin0001]

Hey!
Suppose a part was worth 4 marks, where you had to use the deduced coefficient of friction from the last part. Will I get 4/4 for working out the answer to this part, using the correct method and everything, if I had worked out the wrong coefficient from the last part?
Ty

[saba.ay]

Hey!
Suppose a part was worth 4 marks, where you had to use the deduced coefficient of friction from the last part. Will I get 4/4 for working out the answer to this part, using the correct method and everything, if I had worked out the wrong coefficient from the last part?
Ty

I doubt you'd get 4/4 because there's always 1 mark for getting the right answer. You wouldn't get that mark. There's a chance that you can get consequential marks but I'm not sure how many you'd get with consequential marks.