So did anyone do this? (1 Viewer)

rawrence

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E.g. resisted motion question with jac and fucken gil.

Integrating motion, started the partial fractions and got halfway and thought "nah this won't ever work"

Looking back, I fucking regret stopping.

Did anybody else get halfway and just stop because it looked wrong?!

Fucking.

And if it isn't by partial fractions..AWKIES
 
K

khorne

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E.g. resisted motion question with jac and fucken gil.

Integrating motion, started the partial fractions and got halfway and thought "nah this won't ever work"

Looking back, I fucking regret stopping.

Did anybody else get halfway and just stop because it looked wrong?!

Fucking.

And if it isn't by partial fractions..AWKIES
I quoted:

Integral of 1/(a^2 - x^2) = 1/2a * ln((a+x)/(a-x)), which lead to the right answer/
 

HyperComplexxx

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i did go half way saw that it looked fking messy as fuark so i skipped it....
With a around 20 minutse remaining, i went back to that question and re did it this time correctly :)
you sub in k as mg/vT^2 and from there partial fract the (vT^2/vT^2-v^2)/g
 

D94

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It's similar to Cambridge 4U 7.2 Q2 with the whole partial fractions idea.
 

Nympha

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Yeah I did what you did. Also did that with the f*cking reduction integral in q8. I shouldve continued with it, it wasnt hard. Dammit!
 

zhiying

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Yeah I did it :D but that was probably one of the harder resisted motions around.
 

4025808

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I kinda stopped half way in part ii) ie i simplified it and then I just wrote down what was required to prove :L

it was by partial fractions. that said, too much algebra T_T
 
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anyone know if there is any amount of marks i'd get for 6a) ii and iii

for ii) just got up to the integral 1/(vT^2 + v^2) ... something like that, did some manipulation and abbandoned it
iii) i just did lots of substitution into the equation in ii....then proceeded to skipping it
tnx
 

D94

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anyone know if there is any amount of marks i'd get for 6a) ii and iii

for ii) just got up to the integral 1/(vT^2 + v^2) ... something like that, did some manipulation and abbandoned it
iii) i just did lots of substitution into the equation in ii....then proceeded to skipping it
tnx
I reckon maximum 2, 3 depending on how much of the integration you did.

The algebra/process was where the marks were, imo, not the initial setup.
 

clementc

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Yeah, I just quoted (luckily learnt formula this morning with 5min to go) that that shit = 1/2a ln ((a+x)/(a-x)) or something. Thank god . . . not worth freaking 3 marks otherwise. I think you can quote it if the question is really long, like in this question.

But yeah couldn't get next part. Just abandoned halfway .___.
 

SImon05089

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Sadly, i dont think it's quotable, since it is not in the integral sheet. use of partial fractions to solve the integral only requires 2-3 lines at most
 

D94

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Yeah, I really don't think you can quote that integral, mainly because it's not on the given Standard Integrals sheet, and by extension, not in the Syllabus. The Syllabus does tell you to use partial fractions, and in this case, it was a partial fractions integral.
 

4025808

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='(
*weeps in corner*
but even then, considering that the question required so much working out and algebra, the markers might give you the mark. Also, slyhunter told me that the textbooks have that formula, but the actual HSC doesnt quote it.
 

clementc

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yeah lol the HSC is so dodgy. They have all this unofficial stuff . . . like the sum to product formulae and the angle bisector theorem >__<"
oh well. on to 3 unit maths. joy =\
 

D94

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but even then, considering that the question required so much working out and algebra, the markers might give you the mark. Also, slyhunter told me that the textbooks have that formula, but the actual HSC doesnt quote it.
They have a marking criteria, and they must strictly follow it. If there is a mark allocation for quoting a formula, or using such a formula, then a mark can be given. If there isn't, then the mark cannot be awarded. The algebra is where all the marks were, and 3 marks was reasonable, although I would have liked to seen 4.
 

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