IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => GCE AS & A2 Level => Math => Topic started by: theman on June 14, 2009, 10:17:38 pm

Title: C4 Guesses!
Post by: theman on June 14, 2009, 10:17:38 pm: Hey Guys,

The C4 exam is tommorow anyone have any guesses?

Tips advice, everything is welcome!
Title: Re: C4 Guesses!
Post by: Hwa1 on June 14, 2009, 10:32:46 pm: related rates of change, partial fractions, volumes of revolution, vectors, INTEGRATION
its always the same :P
Title: Re: C4 Guesses!
Post by: theman on June 14, 2009, 10:39:56 pm: Binomial expansion?

Wut bout dat?
Title: Re: C4 Guesses!
Post by: theman on June 14, 2009, 10:41:08 pm: Nd vectors!
Title: Re: C4 Guesses!
Post by: Hwa1 on June 14, 2009, 10:47:15 pm: binomial xpansion is easy :P
Title: Re: C4 Guesses!
Post by: astarmathsandphysics on June 14, 2009, 10:48:23 pm: Binomial exapnsion is not in c4
Title: Re: C4 Guesses!
Post by: theman on June 14, 2009, 10:52:22 pm: Integration and Related Rates of change are the hard ones!

And @astarmathsandphysics, Binomail expansion is chapter 3!
Title: Re: C4 Guesses!
Post by: astarmathsandphysics on June 14, 2009, 10:53:18 pm: Is it in cie a level? Not in ocr/edexcel/aqa
Title: Re: C4 Guesses!
Post by: theman on June 14, 2009, 10:55:10 pm: In edexcel...
Title: Re: C4 Guesses!
Post by: Hwa1 on June 14, 2009, 10:59:10 pm: yeh i agree
integration can get really anoying sometimes
related rates of change are OK SOMETIMES, but usualy a pain in the A**

i jst hope for partial fractions we jst have to do a nice simple cover-up rule :)
i dont want a sort of
a + bx + c/(something) + d/(something else)

or watevr..
Title: Re: C4 Guesses!
Post by: motherheaven on June 14, 2009, 11:16:00 pm: c3 paper was pretty easy .so i have some feeling that c4 paper will be very tough
Title: Re: C4 Guesses!
Post by: Hwa1 on June 14, 2009, 11:27:29 pm: thats wat i was thinkin 2, plz dnt remind me lol
id rather it was the other way round tbh...because a 'hard' c3 is still easy.

guys if u got
ln A = B + ln C
and u wna get rid of the ln's by doin the thing with e
do u do it to the left and right sides as a whole or seperate?
like will it be:
A = e^B + C
OR
A = C x e^B
Title: Re: C4 Guesses!
Post by: motherheaven on June 14, 2009, 11:31:37 pm: it will be
ln A = B + lnC
ln A - ln C =B
ln ( A / C ) = B
A/C = e^B
Title: Re: C4 Guesses!
Post by: Hwa1 on June 14, 2009, 11:34:51 pm: thanks
meh, there was a Q in c3 where we had to factorise something with e's
but i almost fell asleep and startin takin ln's, but that was wrong too because i was doin it to the stuff singularly rather than the sides as wholes...that sucks, 90% in c3 or sumfin im guessin.. :(
Title: Re: C4 Guesses!
Post by: theman on June 14, 2009, 11:35:16 pm: @motherheaven

Yea thts true C3 was pretty easy so they may kill us in C4.

But My S1 was great and C3 too, so hopefully they ll make up!

@Hwa1

B=lnc-lna

B= ln (c/a)

e^B=c/a
Title: Re: C4 Guesses!
Post by: theman on June 14, 2009, 11:36:01 pm: ooops sorry!

motherheaven answered already!
Title: Re: C4 Guesses!
Post by: Hwa1 on June 15, 2009, 08:35:41 am: wat time do u all hav ur exam? mines in 4.5 hours
Title: Re: C4 Guesses!
Post by: Future Doc on June 15, 2009, 09:17:24 am: Quote from: astarmathsandphysics on June 14, 2009, 10:48:23 pm
Binomial exapnsion is not in c4

If you believe that, you might be a little screwed.
Title: Re: C4 Guesses!
Post by: Hwa1 on June 15, 2009, 09:30:39 am: yeh, say goodbye to about 7 marks
omg im so scared, i dnt no half this crap..
Title: Re: C4 Guesses!
Post by: Nabz on June 15, 2009, 09:35:22 am: Mine starts in about 2 hours, wish me luck guys!!!
Title: Re: C4 Guesses!
Post by: Hwa1 on June 15, 2009, 09:39:54 am: I'll be going in like..as soon as u get out, =-(
good luck
Title: Re: C4 Guesses!
Post by: Hwa1 on June 15, 2009, 10:02:24 am: sum1 help me plz
how do u differentiate 12xy implicitly? :s
Title: Re: C4 Guesses!
Post by: Hwa1 on June 15, 2009, 10:04:04 am: dw, did it
product rule lol
Title: Re: C4 Guesses!
Post by: Future Doc on June 15, 2009, 10:10:27 am: do you get 12y + 12xdy/dx?
Title: Re: C4 Guesses!
Post by: Hwa1 on June 15, 2009, 10:12:19 am: yes

omg i studied c4 like 2 weeks ago and thought it was easy
so i started to relax a bit but now i forgot like half the stuff..
integration and related rates of change r gna kill me...
Title: Re: C4 Guesses!
Post by: Mechatronicastronot on June 15, 2009, 11:03:04 am: just remember C4 punishes stupid mistakes, dont do them !

remember all the identities, esp how to use cos (a+b) to form an identity for cos (7x) etc. and how to integrate it.

good Luck to us all,
Title: Re: C4 Guesses!
Post by: theman on June 15, 2009, 07:10:13 pm: ERRRR!!!

THE EXAM WAS RELLI HARD!!!!

Who else is wid me?
Title: Re: C4 Guesses!
Post by: Nabz on June 15, 2009, 08:03:35 pm: Nah it was pretty easy, apart from the shortest distance part in vector, I found the paper easy enough for C4!!
Title: Re: C4 Guesses!
Post by: theman on June 15, 2009, 08:36:12 pm: Relli?

The paper was pretty hard!

Yea the shortest distance one, i didnt get tht aswell i just found the scalar product!

lol