General Thoughts: Mathematics Extension 2 (1 Viewer)

someguy10

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Ellipse gets stretched in the horizontal direction and compacted In the vertical direction since a>>b as e-> infinity. Therefore focii are further apart and asymptotes approach x=0
 
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khorne

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for 7a) sorry to be annoying but how did you guys get this part? pi^ (2/2-2pi) lol i doubt anyone will bother answering this haha I'll just go check terry lee when he finishes his solution :D
Radius = 1-x, so V = 2pi(x)(1-x)/(1+x^2) = x - x^2 / 1+ x^2

so - 2pi int (x^2 - x + 1 - 1 /1+x^2) = -2pi(1 + (-x)/(1+x^2) - 1(1+x^2))

So you get a ln term an arctan term and a x term, which gives you the right answer when you sub in limits
 

zhiying

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Fuck never heard of the reflection property T_T all in all I thought it was harder than last few years, but then again I tend to stress and panic too much in an actual exam :(

Expecting anywhere in the 100-110 range, but hopefully 105+
 

someguy10

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Integrate from 0 to 1 radius (1-x) height f(x). This integral splits into two. A log and a second one. This second one splits into x - invtan(x) after integrating. Leaving 2pi(0.5ln2 - 1 + pi/4)
 

ball00n

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Integrate from 0 to 1 radius (1-x) height f(x). This integral splits into two. A log and a second one. This second one splits into x - invtan(x) after integrating. Leaving 2pi(0.5ln2 - 1 + pi/4)
thanks!!! you're the best! (and I think I got that answer)
 

4025808

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I reckon i did okay in this one. Too much algebra but not as hard in terms of thinking. I attempted 5 c) iii) and then realized it would be too much work, same deal with 6 a) i) (probably will only get 1 mark), didn't get 6 c)
Q7 was a fucking joke this year
Q8 was easier than last years, but the probability was kinda... and who did c) coz I kinda bullshitted in part c) of Q8

and I didn't even know what 8 d) was on about =_=

overall will be expecting around 100/120 for this one.
 
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PhysicsGirl

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Pretty easy exam, just one question was a bit iffy. Expecting around 110-116.
 
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khorne

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Pretty easy exam, just one question was a bit iffy. Expecting around 110-116.
lol

The only maths chicks need to be able to do is ratios...so they can change the amount of ingredients needed for the recipes depending on the servings
 

zhiying

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... get 116 and I will worship you.

Jks not really, math is completely over for me wooooooooooo GL 3uniters
 

HyperComplexxx

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regretting that i should have looked over MX2 more lul
I have very similar questions to those in the paper e.g. probability one and all the conics
Could have easily spent those time doing the last few questions instead of rapping up those questions ^^^
 

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