Iffets' spesh questions

[iffets12345]

So I've finally decided I need to start clarifying alot of questions I have.

1. Acceleration down- positive or negative? I tend to use negative, but sometimes in the question where they're like "SHOW acceleration =*******" it's positive. Do I just do it my way, saying "down= -ve" then switch everything around going "down=+ve" ?

2. Vcaa 2007 spec exam 1 question 7b.
It said "Solve the differential equation given in part a. to find the value of y which is estimated by y2.
VCAA subbed in y2 into the antiderivative. But I thought, when they "value of y estimated by y2" that they meant y3, because you use y2 to get y3 in Euler's.


That's it for now

[x Shane x]

Hey iffets12345,

For acceleration, generally keep down as being negative. However in some cases (as you have come across) the examiners will ask you to take downwards as being positive and I recommend that you follow their instructions in this case, even though it's not what you usually do. Make sure when you do this that you change everything to downwards being positive, I know that occasionally people only change the acceleration and leave initial speed, final speed and displacement as upwards being positive.

And for the VCAA 2007 exam 1 q7b, they are asking you for the EXACT answer, so you don't use Euler's method for this part of the question - all you need to do is antiderive dy/dx, find c, and sub in x=1.2 (as this is the x value that corresponds to y₂, ie. (x0 +2h)). You should get log_e(1.2) +1.

Hope that helps!

[iffets12345]

thanks
Another one:

For vcaa 2008 exam 1,
I wrote 60
the answer , the same as mine in a different form is

Will I lose marks
That number there has a sin (15) involved, I actually had to do a double angle formula to figure it out and I'm not sure how you simplify the square root to get the answer VCAA has.

[98.40_for_sure]

You shouldn't have got a sin 15 at all... all i see is 45 and 30!

[iffets12345]

It's the right answer though
i used lamis triangle and the angle opposite F is 15.

**Oh, I know what you did now. It gives the neater answer, but is mine okay

[98.40_for_sure]

I don't think 90% of spesh kids even know what lami's triangle is so vcaa assumed that you would just resolve forces vert'ly and horiz'ly.

[iffets12345]

are you kidding me, I always use it. Or put it in a vector triangle.

[98.40_for_sure]

are you kidding me, I always use it. Or put it in a vector triangle.

That's why you're getting a 50

[iffets12345]

I will whack you on the head soon too lol Who is the one who got 79/80 on 2009 vcaa exam 2 ?

[98.40_for_sure]

what did you get on 08s?
im going to do them tomorrow along with 06s and a tssm

[m@tty]

I don't think 90% of spesh kids even know what lami's triangle is so vcaa assumed that you would just resolve forces vert'ly and horiz'ly.

This was easy to resolve actually; neat angles as 99.95 said.

[ghadz7]

Is it just me or are the VCAA exams much easier than company ones?

[m@tty]

Weren't you the one who got 37/40 for TSSM '09? Ohh shi...


VCAA are normally easier, from what I've seen - in most subjects.

[iffets12345]

what did you get on 08s?
im going to do them tomorrow along with 06s and a tssm

erm lost four marks in exam 1...
08 is harder than 09, imo.
Doing exam 2 on the weekend. I'm a risk taker.

[ghadz7]

Weren't you the one who got 37/40 for TSSM '09? Ohh shi...


VCAA are normally easier, from what I've seen - in most subjects.

TSSM exam 1s are easy, I couldn't finish exam 2 on time though. The multiple choice questions require alot of thinking. VCAA MC are so straight forward.