how was half yearlies??? (1 Viewer)

[mojako]

Originally posted by Calculon
Thats because your in year 11

I'm having my 0.5 yearlies right now (but of course not at 31 March 2004 11:00 at night) private school btw..
Do you know what's so wrong with this forum's clock?? Can anyone tell the website administrator?

 

[Calculon]

Half Yearlies were heaps good. Got 100% of it out, yay for me!

 

[sammeh]

sitting my 3u half yearly on monday, i'll post a copy of the paper if i can flog one out of the exam room

 

[dawso]

thats great sammeh, only 3 weeks too late!!!

 

[nike33]

they set ours to easy ... i got 100% but so did 4 other ppl lol

 

[aditya]

really.. what school do u goto?

 

[kpq_sniper017]

for the accelerants......

are u doing 4U maths in yr 11???
coz at my school, i did prelim. 2&3U last year (yr 10) on top of the school certificate exam (i had yr10 and yr11 exams at around the same time)......
this year, yr 11, im doing hsc 2&3U
and next year, if i choose to, i can do 4U in yr 12 (but not this year)

u gotta pretty good to do 4U in yr 11.....how many schools let u do that?

 

[Calculon]

Not many I don't think. My school only let us accelerate 2u

 

[Estel]

Better than my school... we're all doing prelim course in Yr 11.

 

[Zarathustra]

This was in my half yearly - can someone post up a worked solution.
Prove that x^n has a minimum turning point for which n is a positve even integer.

 

[DcM]

Originally posted by Zarathustra
This was in my half yearly - can someone post up a worked solution.
Prove that x^n has a minimum turning point for which n is a positve even integer.

let y = x ^ n

y' = nx^(n - 1)
= 0 if x = 0
:. turning pt at x = 0

at x = 1
y' = n ie. y'>0

:. to have minimum pt, at x = -1, y'<0

at x = -1, y' = n(-1)^(n-1)

:. for y'<0, n-1= odd
:. n= odd +1 which is even.

if n<0 then y'>0

:. x^n has min. turning pt if n is positive even integer.

 

[DcM]

keke haven't done these type of max. / min. questions since yr 11

phew..i still remember some of it

 

[CM_Tutor]

Just one minor comment. The conclusion following y' = 0 at x = 0 should be that there is a stationary point at x = 0, not a turning point. It is the test which follows that shows that the stationary point is actually a turning point.

After all, y = xⁿ has a minimum turning point at (0, 0) for n = 2, 4, 6, ... and a horizontal point of inflexion
for n = 3, 5, 7, ...

 

[DcM]

Originally posted by CM_Tutor
Just one minor comment. The conclusion following y' = 0 at x = 0 should be that there is a stationary point at x = 0, not a turning point. It is the test which follows that shows that the stationary point is actually a turning point.

oh yea..oopz...my mistake..keke forgot alreadi how to use the terms.. =( im gonna fail..

After all, y = xⁿ has a minimum turning point at (0, 0) for n = 2, 4, 6, ... and a horizontal point of inflexion
for n = 3, 5, 7, ...

can we just say that tho..cos we know that alreadi..?

 

[CM_Tutor]

Originally posted by DcM
can we just say that tho..cos we know that alreadi..?

No, you'd have to prove it - my comment was aimed at illustrating that a stationary point need not be a turning point.

 

[mojako]

function: x^n
first derivative: n*x^(n-1)
n is a positive integer (2, 4, 6, and so on).
(n-1) is then greater than zero and is an odd number.
When x = 0, the first derivative is zero
When x > 0, the first derivative is positive
When x < 0, the first derivative is negative
So, there's a minimum point at x = 0.

 

[Sarzzabelle]

I did so bad.. but we only had like an hr to do it in so if i'd only had like 30mins more i woulda done way better.

 

[suiyi_z]

we're from smiths hill high school, selective school in wollongong. every accelerant from our school is expected to do 4u in yr 11. we usually don't have many ppl getting 100% raw on 3u paper..last time i got 97 but that was pretty easy paper.
and can i ask...are all the 3u papers in every school pretty much the same level of difficulty or does it vary alot? becuase when its soemthing like the 3u or 4u course the range of difficulty should be the same right? but i know ppl that have got average scaled mark of 90 for schoool marks that got 95 in hsc. they told me it was becuase our school set harder tests..ppl did better in hsc etc. but i'm thinking that there shouldn't be that bigger difference right?

 

[CM_Tutor]

Originally posted by suiyi_z
and can i ask...are all the 3u papers in every school pretty much the same level of difficulty or does it vary alot? becuase when its soemthing like the 3u or 4u course the range of difficulty should be the same right?

It varies alot. A big lot. And, to some extent, it needs to. In an academically selective school, especially one like SGS or JRAHS or NSGHS, you need a harder paper than the HSC to effectively distinguish between the top students in the year...

 

[suiyi_z]

yea i see your point, i just thought that for extension courses especially for maths that the difficulty is supposed to be more streamlined. but i really don't think i've seen any easy papers from our school..our prelim yearlies were shocking, very hard. my freinds from earlier years tell me that our marks will be scaled alot becuase we're selective and most other schools won't do as well as us...well i'm hoping they'll be scaled anyway, i want around 96 for 3u