Carrotsticks' 2014 Extension 1 HSC Solutions (1 Viewer)

mreditor16

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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 :)
 

RIP3U

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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)
 

mreditor16

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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
 

Carrotsticks

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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.
 
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mreditor16

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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??
 

Carrotsticks

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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

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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???
 
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aDimitri

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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
 

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