[Petro_99]

(Original post by skibur)
Has anyone done the Jan12 paper, how did everyone find it?

i found it quite difficult to be honest. hopefully that means an easier june paper!!

[skibur]

(Original post by Petro_99)
i found it quite difficult to be honest. hopefully that means an easier june paper!!

same But the grade boundaries where just normal. But when you think about the type of people who would do FP2 in January you can understand why I think

[Petro_99]

(Original post by skibur)
same But the grade boundaries where just normal. But when you think about the type of people who would do FP2 in January you can understand why I think

really?

it actually didnt look bad, but once you read the questions it wasnt very nice...

[skibur]

(Original post by Petro_99)
really?

it actually didnt look bad, but once you read the questions it wasnt very nice...

I agree, most papers are harder to score better on in Jan though, apart from C1 and C3 I think

[Horchata]

Does anyone know how to get the determinant from the characteristic equation? I did the June 2009 paper and the characteristic equation was

λ^3 - 3λ^2 + 3λ + 7 = 0

So I thought the determinant would be 7 but it's -7?

[skibur]

(Original post by Horchata)
Does anyone know how to get the determinant from the characteristic equation? I did the June 2009 paper and the characteristic equation was

λ^3 - 3λ^2 + 3λ + 7 = 0

So I thought the determinant would be 7 but it's -7?

I was wondering this aswell, but the way I do i do the characteristic equation the number I get originally is the determinant if you know what I mean?

like when I did this question I got
-λ^3 + 3λ^2 - 3λ - 7 = 0 so I just remember that its the unchanged one, not the best way but yeah

[albus]

(Original post by Horchata)
Does anyone know how to get the determinant from the characteristic equation? I did the June 2009 paper and the characteristic equation was

λ^3 - 3λ^2 + 3λ + 7 = 0

So I thought the determinant would be 7 but it's -7?

I got stuck on this question too, remember, when you worked out the characteristic equation, you must have got
-λ^3 + 3λ^2 - 3λ - 7 = 0
then you changed the signs afterwards, well when you use this equation you get det(M)=-7

This is what it says in the report
Most candidates were able to produce a correct characteristic polynomial, although an equation appeared more rarely. Most expanded by the top row,
although expansion by the middle row would have produced an answer more easily. The determinant of M was not so well done: those who worked it out from scratch were generally more successful than those who used the characteristic equation, because most reversed all their signs to obtain a leading coefficient of 1: thus λ = 0 gave –det(M). 1 was another common incorrect answer.

[Horchata]

Thanks both of you

[MHRed]

Good luck everyone!

[albus]

Does everyone's exam start at 1:30

[justanotherposter]

I know I've left this late but what does it mean in the C+jS questions when it has a bracket with an 'n' above a number? How do you convert that to e form? (if you're meant to do that)

[Petro_99]

(Original post by albus)
Does everyone's exam start at 1:30

yes. 2 hours to go

(Original post by justanotherposter)
I know I've left this late but what does it mean in the C+jS questions when it has a bracket with an 'n' above a number? How do you convert that to e form? (if you're meant to do that)

do you mean demoivres theorem? or them annoying questions about geometric/arithmetic sequences?

ahh just looked through notes now;

e^jx=cosx+jisnx
2cosx= e^jx+e^-jx
2sinx= e^jx-e^-jx

if you mean the sequencing then use the first result to come up with a sequence, then work it out to inifinity or to n, the formula for this is in the booklet.

[justanotherposter]

Sorry I wasn't too clear, I understand the whole sequence thing it's this I don't understand:



The bits in brackets, what do they mean? I vaguely remember being told it's to do with binomial but I'm not sure what it does.

[justanotherposter]

Nevermind, didn't realise the mark schemes have examiner reports, it makes sense now

[chingchong]

well i **** the bed on this exam no ive already lost about 20 marks, probs more! the 2 7 mark questions completely messed me over ! How everyone else found it? Last year paper was so simple with grade boundaries at 55, anyone think it will be lower?!

[skibur]

Jesus ****ing christ...

[skibur]

(Original post by chingchong)
well i **** the bed on this exam no ive already lost about 20 marks, probs more! the 2 7 mark questions completely messed me over ! How everyone else found it? Last year paper was so simple with grade boundaries at 55, anyone think it will be lower?!

Hard, very hard for me anyway, I could do most of it but I wasnt confident on so much of it

[shanban]

A=1/2 and b=1/4 for the last question anyone?

[skibur]

(Original post by shanban)
A=1/2 and b=1/4 for the last question anyone?

I got B as 1/4 yeah but I couldnt get A, how many marks do you think I would lose?

[shanban]

(Original post by skibur)
I got B as 1/4 yeah but I couldnt get A, how many marks do you think I would lose?

It was only a 4mark q so I wouldn't think you'd lose more than 2...providing you've shown your method...


I hated the matrices q, b=4? And (if you did it this way) x=lambda y=7/10 lambda -1 z=1 - 8/10 lambda ??