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x_LiNk_x
How many marks do you think I would get if I used A=50 for the last question and solve for t correctly?


lol sad i used 50 too :frown:i didnt even read the question properly tbh, just saw the number 50 and used that :facepalm:
can anyone remember exactly what the two parametric equations were?
Reply 42
Katermerang
can anyone remember exactly what the two parametric equations were?


x = 1-3t y = 1 + 2t^3 I think. Not sure about the +1 in y, but it was definately 2t^3
Reply 43
Greg.
Can anyone remember the parametric equations? Wasn't one 'x=3-t'? Thanks.


x=1-3t so: (dx/dt)=-3 so: (dt/dx)=-1/3

y=1+2t^3 so: (dy/dt)=6t^2


(dy/dx)=(dy/dt)x(dt/dx)

so: (dy/dx)=-2t^2
Rubgish
x = 1-3t y = 1 + 2t^3 I think. Not sure about the +1 in y, but it was definitely 2t^3


Thank you, hopefully there will be follow through marks, I've just realised I differentiated 1-3t to just 3 not -3. :frown: Please please A* If I miss one by doing this I will die of frustration.
Reply 45
joeworrall
x=1-3t so: (dx/dt)=-3 so: (dt/dx)=-1/3

y=1-2t^3 so: (dy/dt)=-6t^2


(dy/dx)=(dy/dt)x(dt/dx)

so: (dy/dx)=2t^2


Thanks. For the last part to find a cartesian equation, I choose the worst one to rearrange, and got a slightly different answer, like:

2(1x)327+1\dfrac{2(1-x)^3}{27}+1

Which I'm hoping is equivalent to the answer in the unofficial mark scheme! :eek: I think it is, so I hope I still get the marks. :smile:
Greg.
Thanks. For the last part to find a cartesian equation, I choose the worst one to rearrange, and got a slightly different answer, like:

2(1x)327+1\dfrac{2(1-x)^3}{27}+1

Which I'm hoping is equivalent to the answer in the unofficial mark scheme! :eek: I think it is, so I hope I still get the marks. :smile:

Thats right. Unless my eyes are decieving me.

I got that but multiplied it out and ended up getting 27y= ..blablbla + 28
How is 27 + 2 28? I hate core maths so much. XD

What did you need for an A*?
Reply 47
Tomato_Soup1992
Thats right. Unless my eyes are decieving me.

I got that but multiplied it out and ended up getting 27y= ..blablbla + 28
How is 27 + 2 28? I hate core maths so much. XD

What did you need for an A*?


I think I did well on C3, expecting at least 95%. So expect I need 85% or so for C4, but don't know for sure!
Greg.
I think I did well on C3, expecting at least 95%. So expect I need 85% or so for C4, but don't know for sure!

ah, I thought you would have done C3 January, but good luck.

I got 80% in C3 so I needed 100% in this XD.
Good thing i dont need the A* in maths XD.
Reply 49
TropLouis
pretty sure it's not :smile:


I hope so :p: , nice offer for medicine at Corpus btw, it's like 1 in 10 applicants if that get in for that isn't it?
Reply 50
Tomato_Soup1992
ah, I thought you would have done C3 January, but good luck.

I got 80% in C3 so I needed 100% in this XD.
Good thing i dont need the A* in maths XD.


Aha ouch. Didn't have much room for manoeuvre then. :p:
Wasn't C3 really hard in January? And don't you need an A* for your Cambridge offer (congrats btw)?
Reply 51
TigerJack
I hope so :p: , nice offer for medicine at Corpus btw, it's like 1 in 10 applicants if that get in for that isn't it?


thanks, nice offer for oxford :smile: which college?
Reply 52
piccolo12345
lol sad i used 50 too :frown:i didnt even read the question properly tbh, just saw the number 50 and used that :facepalm:


Same, that's what happens when you're under exam conditions!
The last part of the vector equation, I worked out the equation of the line that C would be on - but got really dodgy answers after that because im useless at vectors.

Do you reckon I will still get a mark for working out the line equation or have I lost all 4 marks?
Thanks.
Reply 54
8)a) Is definitely (9-0.1t)^2 -1, as that gives 80 when t=0.

I think all the rest I agree with those, which bodes well for me :smile:
Reply 55
Coyerre
8)a) Is definitely (9-0.1t)^2 -1, as that gives 80 when t=0.

I think all the rest I agree with those, which bodes well for me :smile:

slayerspud
...


I've changed 4)a) and 8)a) as they were slip ups on typing into the computer.

Can anyone remember what they got for the Points in the vector question,?
Reply 56
TropLouis
thanks, nice offer for oxford :smile: which college?


Balliol here, just got my reading list fo the summer through today :p:
Reply 57
TigerJack
Balliol here, just got my reading list fo the summer through today :p:


they don't come better than balliol :smile: that is fairly epic. fingers firmly crossed that a reading list doesn't find it's way through my door. lengthy i imagine?
Greg.
Aha ouch. Didn't have much room for manoeuvre then. :p:
Wasn't C3 really hard in January? And don't you need an A* for your Cambridge offer (congrats btw)?

It wasn't that bad, I just had a really prolonged dense moment (1hr and a half to be precise XD). I made so many stupid mistakes and on the 'hardest question' I got it wrong because I forgot how to differnetiate XD.

Thanks, though the offer was A*AA, it was in F maths, Physics and chemistry.
So it doesn't really matter how I did today. Today was just for fun...

EDIT: You were in the Cambridge thread at one point, I swear. Did you get an offer?
MackaBizzle
I've changed 4)a) and 8)a) as they were slip ups on typing into the computer.

Can anyone remember what they got for the Points in the vector question,?

(3,-1,3), (-1,-1,1)

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