OCR (not MEI) C1 13/05/13

I couldn't find a thread for this so I figured I'd make you guys one.
Good Luck with your exams (If you're reading this before the exam starts.)- I'm sure it went well.
To the best of my knowledge there aren't any rules regarding discussion of OCR Exams so talk away :smile:

If you want to make an “unofficial mark scheme” , just quote me and I’ll set up links in the OP for you all to have a look at.

MrM's C1 13/05/13 OCR (Not MEI) Solutions

Just some people's thoughts: - If you can remember a question, post it and I'll answer.
Q1:

Spoiler

Q10:

Spoiler

The whole lot . . .

Spoiler

Paper's part way down page 14.

(edited 10 years ago)

Scroll to see replies

Reply 1

joostan

Original post by Pras123

How did you find it?

Its not been taken yet . . . :redface:

Reply 2

Han456

What did people get for the last question? For the point A?

Reply 3

Mr M

Study Forum Helper

I am in a meeting until 6 p.m. but will post the answers once I get home.

Reply 4

Bohla

Original post by Han456

What did people get for the last question? For the point A?

(-2, -27) here

Reply 5

queketth

Original post by Bohla

(-2, -27) here

SNAP

Reply 6

John Dogg

Original post by Han456

What did people get for the last question? For the point A?

(1,0) what about you ?

Reply 7

eggfriedrice

Original post by Han456

What did people get for the last question? For the point A?

I got two points, (-9,0) and (-2,-27).

Reply 8

cheetahs56

Not seen it anywhere, how did you guys find it??

Reply 9

Ecomax

Got two points for A, was i supposed to pick one of the two or?
Had k=-5

Reply 10

queketth

What was the question again I just recognise the (-2,-27) but don't remember the actual question

Reply 11

nicked95

Original post by eggfriedrice

I got two points, (-9,0) and (-2,-27).

but (-9,0) did not fit into the first equation so i thought only (-2,-27) was the answer

Reply 12

John Dogg

ffs was the factored version equal to -4. I had plus 4 :frown:

Reply 13

queketth

Original post by nicked95

but (-9,0) did not fit into the first equation so i thought only (-2,-27) was the answer

Thats exactly what my logic was because its a tangent to the curve at (-2,-27) yes at the other point the gradient was the same but it did not intersect the curve so my belief is its just the (-2,-27) point

Reply 14

Z.M.1

What value did people get for k? And how?
I expanded the brackets, then differentiated it and said when dy/dx = 0 its a stationary point, then subbed in x=-3 and found k to be 49. I know that's wrong but would I get any method marks? Thanks :smile:

Reply 15

queketth

Original post by Z.M.1

That sounds very similar indeed to my method but I got -5 I think that there was probably an issue with your expansion that just threw it off cant promise anything but pretty sure you will pick up some marks !

Reply 16

John Dogg

Original post by Z.M.1

Exactly the right method i think. just a wrong calculation somewhere so you should get method marks.

Reply 17

eggfriedrice

Original post by nicked95

but (-9,0) did not fit into the first equation so i thought only (-2,-27) was the answer

Ah I did not think of that. :tongue:

you're probably right.

Reply 18

Lilhazzaman

Original post by Z.M.1

I did the same... But got k=+5
I then got (1,0) as my coordinate.

Reply 19

BankOfPigs

If I recall, you got a nice quadratic in that question, by dividing by 1-x then rearranging into (x+2)^2 = 0

I got -2 -27 as well, since it was meant to be tangent I'm pretty sure it was meant to only have one point.

I think there are two methods for finding k, which i got as -5.
You can either use the formula and get 18 = 6+-root84-12k, which gets you k as -5, or sub it into the dy / dx equation with x as -3.