Competition - post a photo you've taken of nature >>

C3 June 2012 - Post Exam Thread - Solutions and Paper in the FIRST POST

Scroll to see replies

I did that! but then realised I could divide everything by cosx

Question: i divided everything by cos3x also but if you can do that are you not able to take it out as a factor, leaving you with cos3x = 0 and get more results??

Reply 101

shooby_doo

Original post by Kenan and Kel

I'm thinking..

100 74
_90 66
_80 58
_70 51
_60 44
_50 37
_40 30

Bit low ..

Reply 102

IxI_Rhys_IxI

Original post by Arsey

prob 2

Hey, on Question 3, during my product rule, I incorrectly differentiated Sin3x as Cos3x rather than 3Cos3x... Looking at the rest of the question, that was the only mistake I made... How many marks would I lose, despite ECF marks?

Reply 103

The_Pen

Also for 8c, I managed to get the sin2x but due to time finishing, I could not complete the rest of the paper, will I at least get 1 mark for 8c?

Reply 104

shooby_doo

For the iteration I left one of the answers as root 2 :s-smilie:

Reply 105

pranav?

WAHH 8b isnt it 173.5 and 113.5 NOT 173.1, 113.1 ?!!!

Reply 106

Dentistry:)

Do you guys think youd get an ecf mark for the very last question?

I said c = -7, and then the maximum value was 18 :/

So would i get ecf from 8c for 8d?

Reply 107

Mr Tough

Original post by Brainiac

Overall a good paper I think, not harder or easier than any past papers...

Did anyone think Q5 a and b should have just been one 6 marker, i ended up doing a only to realise I had answered b the had to work out which part of the solution was a and which was b?

couldn't agree more, my entire year group came out annoyed at the fact that we didn't know where to end a and start b! poor question really

Reply 108

Mr Tough

Original post by pranav?

WAHH 8b isnt it 173.5 and 113.5 NOT 173.1, 113.1 ?!!!

nope, maybe you've used rounded answers?

Reply 109

Arsey

Original post by emily24

I can't view the ms file all I get is arsseys water Mark any help please??

got to adobe.com website and download reader x.

your version of acrobat reader is out of date.

Reply 110

Arva

Original post by Arsey

my guess is in the first post

I'm praying the boundaries are slightly lower than that - 95 UMS makes me worried about not getting an A* overall. Thanks again!

Reply 111

Puloot

NUUU, i forgot to draw the asymptotes ! I think i lost around max 15 marks. well, still an A. I hope so!!

Reply 112

tom28

It's depressing to see that 3a was so easy. I ended up writing 2 pages of working, but at least it got me the right answer :tongue:

Reply 113

bowersbros

Couple of questions:

For 2, c)

I did
f(1.2715) and f(1.2725) but it didn't actually do anything.

It gave me a final answer (when placed in the function) of 1.2719 and 1.2732 respectively, so I stated that it would round.

Would i get any marks for using the correct numbers and just losing the one for calculation?

For 7,a,i)

I got

(x^1/2)xln(3x)
---------------
2

Is that the same as in this? (Im too tired to work it out now, and can't tomorrow due to being at an edinburgh openday all day)

For 7,b) I got

6cos^2(tan^-1(x/3)/2) because i missed it was 2y

Thats as far as I took it.

How many marks would I get for that? I assume either 2 or 3.

For 8,b) I got x = 6.86 and 173.1

Would I lose just 1 mark for putting an extra incorrect value?

Thanks :smile:

Reply 114

EatRainbows

Original post by pranav?

WAHH 8b isnt it 173.5 and 113.5 NOT 173.1, 113.1 ?!!!

You're wrong. ):

Reply 115

zincoff

I used double angle formula for question 3)a) instead of simplifying to tan x, but I got the right answer from this. Do you think I'll lose any marks?

Reply 116

tangkykiet

everyone please help . Question 7b , what if i change sec2(2y)=1+tan2(2y)
dx/dy=6(1+tan2(2y))
dx/dy=6+6tan2(2y)
dx/dy=6 + 3tan2y(2tan2y) and then i turn x and then i switch upside down . Would i get at least 3 marks out of 5 ?

Reply 117

icedragon

Original post by pranav?

WAHH 8b isnt it 173.5 and 113.5 NOT 173.1, 113.1 ?!!!

Nope, you must have rounded wrong.

Reply 118

tommyridges

Original post by Brainiac

I did the same! I got all the way to 1/cos^2(theta) and then read part b) and realised i'd practically done it all :L It shouldn't matter though, they didn't say how far to simplify to so as long as you get b) right you should get the marks for a) I think :biggrin: