General Thoughts: Mathematics Ext 1 (3 Viewers)

[AlexJB]

yer i couldnt find the area...

tan60 = o/h
o = h * sqr.rt(3)

Area of total triangle = 2 * (0.5 oh)
= oh
= h^2 * sqr.rt(3)

Volume = 10h^2 * sqr.rt(3)

---

I think that was the answer.

 

[untouchablecuz]

hey guys i got pi/4n for 5a)iv)
dx/dt = nroot(a^2-x^2)
then sin-1 (x/a) = nt
then x= asin(nt)
then particles speed is half maximum speed at (a/root2)
so sub a/root2 in then you get pi/4 = nt no?

i got

x=asin(nt)

v=ancost(nt)

max v = an

.'. an/2 = an cos(nt)

cos(nt) = 1/2

t=pi/(3n)

 

[copeys]

You had to find the area of the triangle and then just multiply by 10.

This is what I did: was isoceles. Construct a line through the middle, form 2 equal right angled triangles. We know the height is h, and we know the angles of the triangle. Use trig to find out the length of the base of the triangle. That gives you 2 sides, which you can use to find the area, which you just multiply through by 10.

Did exactly that

 

[AlexJB]

i got

x=asin(nt)

v=ancost(nt)

max v = an

.'. an/2 = an cos(nt)

cos(nt) = 1/2

t=pi/(3n)

And that is correct.

 

[untouchablecuz]

anyone notice that dV/dh = A

pretty cool

 

[mitchwong650]

tan60 = o/h
o = h * sqr.rt(3)

Area of total triangle = 2 * (0.5 oh)
= oh
= h^2 * sqr.rt(3)

Volume = 10h^2 * sqr.rt(3)

---

I think that was the answer.

Exactly what i did.


Q1-4 only took around 30 minutes, Q 5 things started going down hill, but things got a bit better with the projectile question..

binomials raped me hard (except induction i think i got that)

hoping for 60+/84

 

[lisarh]

i got

x=asin(nt)

v=ancost(nt)

max v = an

.'. an/2 = an cos(nt)

cos(nt) = 1/2

t=pi/(3n)

HI-5 i got that tooo!!!

 

[micuzzo]

tan60 = o/h
o = h * sqr.rt(3)

Area of total triangle = 2 * (0.5 oh)
= oh
= h^2 * sqr.rt(3)

Volume = 10h^2 * sqr.rt(3)

---

I think that was the answer.

looks good... i tried it too.... n failed!

 

[aznvdz]

OMG THERE GOES MY 99.95 atar.

 

[lychnobity]

For 5biv) what did everyone get?

I had k in my answer everywhere for some reason...

And 6aiii) where did you have to substitute?

6biii) no idea how to get (2n-1)

7cii) Didn't even get to do it.

Other than that, everything else was good.

 

[imoO]

I just hope I am still in the top 30% of the state so I can get the ATAR I wanted.

 

[AlexJB]

For 5biv) what did everyone get?

I had k in my answer everywhere for some reason...

And 6aiii) where did you have to substitute?

6biii) no idea how to get (2n-1)

7cii) Didn't even get to do it.

Other than that, everything else was good.

5biv, think it was just k?
6aii, equate the 2 y equations, you're able to find an expression for t and show that that value equaled th4e value in part i.
7cii, lost a couple of marks on 7c, going to go do it again in a bit, will get back to you if nobody else has.

Oh, and 6biii, I think you had to split it up in to two separate series, use the result in part i, then simplify? Pretty sure that's what I did, and the answer came out nicely.

 

[kanux]

Q 1-4 was surprisingly easy
got screwed over for 5, 6, 7 ><"

 

[buildabridge]

It was harder than the past papers I've done but ok I guess. It seemed very long, like usually I would finish in 80 mins and it took me half an hour longer today.
I'm thinking around 75/84.

 

[liz91]

As soon as we got out I just looked at my friends and started laughing.....ah it was SO bad it was funny - THIS is EXACTLY why 13 units is a good idea

What did people get as the max value of theta in the first part of question seven? I'm not sure my derivation was right - ahhhhh inverse trig functions drive me crazy!

Woah. I never have to do any ever again. Compensating factors!

 

[Mrazism]

74-75 if no silly mistakes~~

 

[5647382910]

im pretty sure ill get 75+ with max at 80/84

That tank q (5b) screwed me for some reason
Was the max value of theta sqrt(a(a + h)) for q 7bii? was 7cii sqrt(ah)?
also, could someone please explain why if P is on T, theta is max

 

[lychnobity]

As soon as we got out I just looked at my friends and started laughing.....ah it was SO bad it was funny - THIS is EXACTLY why 13 units is a good idea

What did people get as the max value of theta in the first part of question seven? I'm not sure my derivation was right - ahhhhh inverse trig functions drive me crazy!

Woah. I never have to do any ever again. Compensating factors!

I got 1 + square root of something

 

[Fortify]

Hello E1 ! D:

 

[untouchablecuz]

im pretty sure ill get 75+ with max at 80/84

That tank q (5b) screwed me for some reason
Was the max value of theta sqrt(a(a + h)) for q 7bii? was the final 7cii sqrt(ah)?
also, could someone please explain why if P is on T, theta is max

for 7 c) ii)

let O be the bottom of the wall

OT²=OR*OQ

OT²=h(a+h)

OT=√h(a+h), OT>0