Carrotsticks' 2014 Extension 1 HSC Solutions (1 Viewer)

[Carrotsticks]

That is fine, you are just re-proving the result from part (i).

You might lose a mark for saying "A pattern is emerging". It's an Extension 1 paper not a damn movie trailer.

 

[aDimitri]

Trying to cram the other method of doing the locus problem into the gap on page 10, fingers crossed that it can fit!

for that question, i showed distance QS = a, not quite as elegant as braintic's solution but it worked

 

[Kurosaki]

Haha 'A pattern is emerging'.

 

[aDimitri]

That is fine, you are just re-proving the result from part (i).

You might lose a mark for saying "A pattern is emerging". It's an Extension 1 paper not a damn movie trailer.

laughed at this

 

[mreditor16]

That is fine, you are just re-proving the result from part (i).

You might lose a mark for saying "A pattern is emerging". It's an Extension 1 paper not a damn movie trailer.

lol so is it a full-proof solution? are there any weaknesses in it? asking since they differentiate state-rankers by the quality of their working, and I think I have a chance

 

[shreyansprasad]

For MC q7, why cant B be the answer?

 

[RIP3U]

OKAY HOLD UP BOYS.

I GOT A QUESTION.

QUESTION ELEVEN B (rain)

The question asks that you "write an expression for the probability that it rains on fewer than 3 days in November"

Considering this, i only worked out P(1 days) + P(2 days) since with (0 days), it doesn't rain, thus shouldn't be included in the probability that it "rains on fewer than 3 days".

THOUGHTS? (pls i wouldn't mind not losing a mark trollface.jpg)

 

[Kurosaki]

For MC q7, why cant B be the answer?

try integrating, you will see that the amplitude is not 5.

 

[mreditor16]

OKAY HOLD UP BOYS.

I GOT A QUESTION.

QUESTION ELEVEN B (rain)

The question asks that you "write an expression for the probability that it rains on fewer than 3 days in November"

Considering this, i only worked out P(1 days) + P(2 days) since with (0 days), it doesn't rain, thus shouldn't be included in the probability that it "rains on fewer than 3 days".

THOUGHTS? (pls i wouldn't mind not losing a mark trollface.jpg)

lol mindgames

 

[mreditor16]

lol so is it a full-proof solution? are there any weaknesses in it? asking since they differentiate state-rankers by the quality of their working, and I think I have a chance

Carret?

 

[Kurosaki]

dat username

I think you just ripped everyone's 3u

nah srs I'm pretty sure "fewer than 3" includes 0 because... by the principle of mathematical induction 0 < 3 for all values of n.

st8 rank right there

 

[Kurosaki]

Carret?

I reckon it's fine if that means anything =).

 

[Carrotsticks]

for that question, i showed distance QS = a, not quite as elegant as braintic's solution but it worked

I really hope that students using the same method as the one braintic demonstrated were not penalised for stating things such as the gradient of the tangent at P being t and the reflection property, without proof.

lol so is it a full-proof solution? are there any weaknesses in it? asking since they differentiate state-rankers by the quality of their working, and I think I have a chance

Yes, the solution is 'fool-proof'. However, it seems like your spelling isn't =)

OKAY HOLD UP BOYS.

I GOT A QUESTION.

QUESTION ELEVEN B (rain)

The question asks that you "write an expression for the probability that it rains on fewer than 3 days in November"

Considering this, i only worked out P(1 days) + P(2 days) since with (0 days), it doesn't rain, thus shouldn't be included in the probability that it "rains on fewer than 3 days".

THOUGHTS? (pls i wouldn't mind not losing a mark trollface.jpg)

That will get you one mark out of two.

Oh never mind, I skimmed and thought your justification was for why 0 was to be included, not why 0 is NOT to be included.

You may or may not get a mark. Leaning towards not.

 

[mreditor16]

Yes, the solution is 'fool-proof'. However, it seems like your spelling isn't =)

lol lol lol my bad

 

[mreditor16]

thanks kuro <3

brb calculating the binomial probability of my 3u state rank!!!!!

0?

 

[mreditor16]

Carret, how do they determine the order of state rankings? especially if they all got the same raw mark??

is it true they compare the quality of working out??

 

[Kurosaki]

Friend asked me this:

If I used auxiliary angle and then products to sums for Q 14 (iv) from part (ii), and then quoted that , to show max D has a max value would that be accepted?

 

[Carrotsticks]

Carret, how do they determine the order of state rankings? especially if they all got the same raw mark??

is it true they compare the quality of working out??

I cannot say anything with absolute certainty.

Friend asked me this:

Difficult to say because D in fact has many maxima/minima, just need to find the one in the right domain. I'm not sure if your friend made that connection.

 

[bio4lyf]

for one of the integration questions (3 marks) i wrote 1/2 in front instead of 2 which was the rite answer..... how many marks am i going to lose???

 

[aDimitri]

I cannot say anything with absolute certainty.



Difficult to say because D in fact has many maxima/minima, just need to find the one in the right domain. I'm not sure if your friend made that connection.

i showed that f(pi/6) > f(pi/3) and f(pi/6) > f(0) so there must be a max between 0 & pi/3
then showed there was 1 stationary point in that domain, therefore a max