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

Qualification => Subject Doubts => GCE AS & A2 Level => Math => Topic started by: hdbkiwi on June 06, 2009, 09:54:51 am

Title: C1 & C2 Discussion here!
Post by: hdbkiwi on June 06, 2009, 09:54:51 am: So now that it's been a day, we can discuss!
How did you find C1 and C2?
I found C1 to be great; C2 I had one question with solving the trigonometric equations... how did you guys find it?
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 10:07:24 am: which part of the trignometric question ...
i made the stupidest mistake :P the question where they asked write down f(k).... i just made k the subject and showed it :p ... we had to put k in as x though..
justloosing tht mark ... otherwise C2 was pretty straight forward...
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 06, 2009, 10:09:32 am: Ah well you'll only lose a couple marks-still great :)
The question with (1+tanx)(Sinx+...(was it 5?))=1(can't remember this side either lol)
what did you do for that?
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 10:13:01 am: equate each bracket to 0
nd continue with the sum
1+tanx= 0
tan inverseof -1 ... and continue :P
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 06, 2009, 10:20:45 am: ahh good good.. so solve for sin and tan and then get all the different values between -180 and 180?
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 10:22:31 am: yes tht s all.. four answers u wud get

did u find nythign tricky in tht paper other than tht ?
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 06, 2009, 10:27:29 am: Hmmm don't think so. How about you? Did you take any other Modules for Math?
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 10:29:19 am: S1 C2 and C1 ... but C1 i gave in jan
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 06, 2009, 10:33:01 am: Oh okay-I did M1 in Jan and also did M2 this June- what's the S1 like?
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 10:36:34 am: S1 is more of graphs nd mean mode median range sh*t
lots nd lots of formulaes... i m doign M1 next eyar ...in june ..is it easy or reallly hard lik i hear form ppl
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 06, 2009, 10:46:55 am: I think it really depends on your teacher-they basically ask the same questions each time, so if you know how to solve the questions you'll be fine. I had a teacher from cambridge who had a degree in physics ;D so I was really lucky to have him and got 100 UMS; hopefully same for M2 this time round-for C1/C2 I had a horrible math teacher (this other dude) so I had to learn it all by myself; so probably won't get 100 in C2-hope I do though! :) M1 is basically about forces and moments and momentum-lots of fun haha :)
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 11:03:58 am: C2 u got the trignometric stuff right ?
Title: Re: C1 & C2 Discussion here!
Post by: bilal920 on June 06, 2009, 12:19:09 pm: Does any1 remember the integration question the 1st one
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 12:29:41 pm: 29 was the answer
waht did u get
Title: Re: C1 & C2 Discussion here!
Post by: mezzbe on June 06, 2009, 12:35:43 pm: C1 was okay the only problem i had was that my answers were never intergers i always got like mixed fractions and like top heavy fractions and stuff so C1 I dont think i did that great. But C2 was better than C1 even though i got stuck on the trig question buh i manage to do it all with with minutes to spare at the end so hopefully that will turn out to be great.
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 12:36:37 pm: did u get any of r answers as -45 in the first part of trig question in C2
Title: Re: C1 & C2 Discussion here!
Post by: bilal920 on June 06, 2009, 12:37:48 pm: yes - 45 and two more
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 12:44:16 pm: 3 more :P there were 4 answers
Title: Re: C1 & C2 Discussion here!
Post by: bilal920 on June 06, 2009, 12:47:30 pm: true no i meant for only tan theta
Title: Re: C1 & C2 Discussion here!
Post by: mezzbe on June 06, 2009, 12:48:20 pm: :| i got 45 and 1 more...damn
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 12:51:26 pm: oh :O howcome ? what did u do /
Title: Re: C1 & C2 Discussion here!
Post by: bilal920 on June 06, 2009, 12:53:39 pm: does any1 remember the 1st question and by that i mean the question and not the anser
Title: Re: C1 & C2 Discussion here!
Post by: mezzbe on June 06, 2009, 12:54:24 pm: i dont even know i remeber i did so much stuff and got to part tan theta=-1 and i got theta as 45 and then drew that CAST circle thing and checked where tan is negative and got the answers as 125 and 315...i dont remember it properly thougb
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 01:01:06 pm: question i know the limits were 4 and 1 :P
Title: Re: C1 & C2 Discussion here!
Post by: mezzbe on June 06, 2009, 01:03:03 pm: okay maybe am thinkin bout a different question then
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 01:08:06 pm: oh no i m talking abt the first question:P
for bilal 920
Title: Re: C1 & C2 Discussion here!
Post by: mezzbe on June 06, 2009, 01:10:22 pm: loooooool..klkl
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 01:15:40 pm: lol
yea :D
Title: Re: C1 & C2 Discussion here!
Post by: bilal920 on June 06, 2009, 01:17:37 pm: kk thanx but i still need the eqn lol
oh and in the function of k part was the anser -8
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 01:20:52 pm: yea it was ....
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 06, 2009, 06:07:01 pm: The answers for the trigonometric identities (part a) were:

For tan x part: -45 and 135

For sin x part: 23.6 and 156.4

;D ;D ;D

Any other questions???
Title: Re: C1 & C2 Discussion here!
Post by: onhsa on June 06, 2009, 08:51:22 pm: So, everyone, did you fall for THE TRICK?
Well, we all know how "easy" 4sinx=3tanx was. But what of the hidden agenda Edexcel so kindly cooked up for us? The ones who think have gotten it "right" did this:

4sinx=3(sinx/cosx)
(4/3)(sinx)(cosx)=sinx
(4/3)(cosx)=1(sinx/sinx)
(4/3)(cosx)=1
cosx= 3/4
and they found values for x

however, we have missed out alot of the question... keep reading

$correct:$

4sinx=3(sinx/cosx)
4(sinxcosx)=3sinx
4(sinxcosx)-3sinx=0
sinx(4cosx-3)=0
sinx=0
& then find values for sinx=0 as well
cosx=3/4
find values of cosx

So we have missed a part of the question, please post what u've done here, cos if no one's gotten it right fully, they may accept the incomplete version as a correct answer.
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 06, 2009, 09:47:22 pm: in c2 paper wat was anyone lograhtim question second part answer
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 09:58:22 pm: my friend got it the right way
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 06, 2009, 10:03:20 pm: what was the answer anyone remember
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 06, 2009, 10:04:57 pm: plzzz anyone tell
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 10:05:23 pm: 8 and 1/8
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 06, 2009, 10:08:28 pm: how answer can be 8 . can u tell me that log 2x + log 2x = 2log 2x can be possible.can u plzz write down all the steps
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 10:10:25 pm: it wud becum log2x X log2x
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 06, 2009, 10:15:27 pm: i m getting square root of 512
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 06, 2009, 10:17:40 pm: ok in c2 paper in trapezium rule question what was the answer overestimate or underestimate.plzzzz reply
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 06, 2009, 10:24:47 pm: overestimate
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 06, 2009, 10:28:04 pm: thnxxx and in c1 paper there was one question of sketching graph in part b) we have drawn the graph what were we suppose to do in c) which was a very long equation.like (x-2)whole cube..................plzzz reply
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 07, 2009, 08:33:21 am: Translate it in the x-direction +2 units.
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 07, 2009, 08:49:28 am: @onhsa....how many marks may we lose for that?
Title: Re: C1 & C2 Discussion here!
Post by: bonny92 on June 07, 2009, 09:04:57 am: what was the reason for overestimate?
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 07, 2009, 09:16:15 am: Reason: Excess area above the region R was taken by each strip (trapezium) made in the exponential curve.
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 07, 2009, 09:17:03 am: @onhsa....how many marks may we lose for that tricky trigonometric question?
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 07, 2009, 10:09:56 am: 3 marks weshud be loosing
and the reason for the overestimate cud also be the curve shifts inwards ...
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 07, 2009, 11:10:31 am: The first question: S(2X+3X^(1/2)) (upper value 4; lower value 1) for C2
you get 29
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 07, 2009, 06:39:02 pm: in c1 paper wat was the area of triangle OCB in one question last part
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 07, 2009, 07:56:42 pm: Quote from: motherheaven on June 07, 2009, 06:39:02 pm
in c1 paper wat was the area of triangle OCB in one question last part
Area Triangle=1/2(b)(h)
=.5(23/5)(8 )
=18.4
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 07, 2009, 07:57:28 pm: and it's 23/5 because the y-intercept (C) was 23/5
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 07, 2009, 10:06:07 pm: thnxxx i got the same answer
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 07, 2009, 11:05:33 pm: can anyone tell me the minimum value of r and the minimum value of surface area in c2 paper last question
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 07, 2009, 11:21:53 pm: 281 or 280 for surface area
nd for r i think 6.5565 or smethign similar i dnt rmember :S
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 08, 2009, 12:04:39 am: answer for my surface area was 280 and my value for r was 9.5565. and in c2 paper the question in which we have to apply trapezium rule to find the area .what was the area i was getting about 6.133
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 08, 2009, 11:36:21 am: Your answer is right motherheaven. :D
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 08, 2009, 12:05:47 pm: The curves are going to be low this time....I wish so... ??? ??? ???
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 08, 2009, 02:40:07 pm: I have my answers in the formula booklet that they let me keep after the exam lolz^^
So once I get home if anyone needs any specific questions I most likely have them down :)
Title: Re: C1 & C2 Discussion here!
Post by: bilal920 on June 08, 2009, 02:49:56 pm: the unofficial markscheme is in here
http://milanmehta.net/maths/c2.html
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 08, 2009, 02:53:42 pm: Quote from: bilal920 on June 08, 2009, 02:49:56 pm
the unofficial markscheme is in here
http://milanmehta.net/maths/c2.html
awesome thanks for finding that site mate +rep for you :D :D
Title: Re: C1 & C2 Discussion here!
Post by: nzpd9 on June 08, 2009, 03:24:39 pm: :S r u sure the answer for the log Q is right ?
i got +-root 512 ..
Title: Re: C1 & C2 Discussion here!
Post by: Orichee on June 08, 2009, 05:28:58 pm: i did the stupidest mistake.... instead of taking 0.5 (h) i took it 1 :( in that trapezium role question ... n i got stuck in that trignometry question first one ...da rest was ok...
Title: Re: C1 & C2 Discussion here!
Post by: bilal920 on June 08, 2009, 05:40:11 pm: who removed my rep and for wat goddamn reason
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 08, 2009, 08:00:45 pm: Quote from: bilal920 on June 08, 2009, 05:40:11 pm
who removed my rep and for wat goddamn reason
wasn't me but have some more ;D
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 08, 2009, 08:12:23 pm: Ah and C1 TOO THANK YOU SO MUCH bibal is that your site??
Title: Re: C1 & C2 Discussion here!
Post by: motherheaven on June 08, 2009, 09:23:17 pm: c1 paper is locked can anyone tell password
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 08, 2009, 09:31:10 pm: Quote from: motherheaven on June 08, 2009, 09:23:17 pm
c1 paper is locked can anyone tell password
yeah it is for me too mate-gotta ask bilal I guess :)
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 09, 2009, 10:01:17 am: I can't open the paper, please help
Title: Re: C1 & C2 Discussion here!
Post by: mezzbe on June 09, 2009, 10:42:20 am: damn my answers were nothing like the ones on that markscheme...thats one A gone :(
Title: Re: C1 & C2 Discussion here!
Post by: nzpd9 on June 09, 2009, 10:59:45 am: i lost 16 marks :'(.cuz i left ALL of Q7..
do u guys think 59/75 can still be an A if noone actually got full marks ?
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 09, 2009, 11:15:24 am: seeing reactions from soo many students :P
ur mark shud make lik 82%... so u r still on for an A mate :D

thresholds are bound to fall
Title: Re: C1 & C2 Discussion here!
Post by: nzpd9 on June 09, 2009, 11:19:03 am: thanks :)
yeah 82% is an A ..but i could have other silly mistakes,,
im not sure abt the log Q. i got +-root512 and some pple got 8 nd 1/8 or smthing,,
so :-\ it might be more than 16 marks,..
Title: Re: C1 & C2 Discussion here!
Post by: master786 on June 09, 2009, 11:56:02 pm: ur answer is rong the answer is 8 and 1/8

the answer u got if u put it back in the eqn as x... u wont get the answer
Title: Re: C1 & C2 Discussion here!
Post by: nzpd9 on June 10, 2009, 10:58:28 am: yeah it iss wrong,,
im gna resit c2 cuz i kno i can do waaay better..
Thanks anyways
Title: Re: C1 & C2 Discussion here!
Post by: omega007 on June 10, 2009, 11:10:54 am: What are the passwords??? ??? ??? ???
Title: Re: C1 & C2 Discussion here!
Post by: hdbkiwi on June 10, 2009, 11:41:11 am: bilal hasn't been active for the past couple of days-hopefully he'll come on soon and tell us :)
until then...we wait :) but if you have any questions for the C1 the paper is actually in the marking scheme-you just look at the first line of every question (well most questions of the exam were on there)
Title: Re: C1 & C2 Discussion here!
Post by: bilal920 on June 13, 2009, 08:40:14 am: sorry ppl but i have tried and tried again but i cant access the C1 paper. So sorry but its not my site so i hope u will accept my apology. Thank u
Title: Re: C1 & C2 Discussion here!
Post by: astarmathsandphysics on June 13, 2009, 08:44:59 am: here are c2 and s1 papers