OCR (not MEI) C1 - Wednesday 13th May 2015

Dammit, I put that but convinced myself out of it

I thought that as the equation has no real roots, and the x^2 was positive, so k couldn't be a minus number, so put k>8/25...
I don't know... Cant do anything about it now :P

Reply 221

Maprunner

Original post by AlfieH

It was ^-4/3 not ^4/3, no?

makes no difference, just means it's 1/16

Reply 222

Parallex

6

Original post by AlfieH

It was ^-4/3 not ^4/3, no?

I meant that :tongue:

Reply 223

username1006802

5

Original post by Parallex

Me and my friend were saying it's an odd function so both are acceptable?

That's what I've been thinking if the question was asking for y = -1/(3x)

Reply 224

c223

OP

2

Can't remember the question order so sorry if it's wrong (it's definitely wrong). From what I can remember:
1) 4 + 4root3
2) can't really describe the graph, if you know what y=1/x looks like then reflect in either axis.
Translation of 2 in x was -1/(x-2)
The translation they wanted you to state was a stretch of 1/3 in either axis.
3) 5^8
5^(-1/4)
5^(9/2)
4) was this the one with k?
Factorise the quadratic, draw graph. For y>0, x<-1 or x>3/2
K < -25/8
5) differentiation? Can't remember the answer to this, was reasonably straight forward though if you expanded brackets (or product rule from C3)
6) simultaneous equation - x=2, y=1 or x=14/3, y=-13/3? Not sure about signs, think this is right though.
7) differentiate x^(-1/3)? Should get out -1/48 when you put x in.
8) coordinate geometry? Line was something like 6x-8y-29=0
9) a=13
Second derivative was positive therefore min points
X=1/3
10) centre (5,-2) radius 5
Prove tangent
Area of triangle = 40
I've just realised how much I really cannot remember the order. These are my answers which seem to be generally accepted within my school and by various people on here. They may not be right.

(edited 8 years ago)

Reply 225

Oikai

everyone reply to this their predicted grade boundary for an A please :wink:

Reply 226

Spriggs3

What do you guys think the raw mark for full UMS will be?

Reply 227

Parallex

6

2014 was 65/72 this was *probably* a little harder than 2014 (2014 was a joke)

guessing 61/62 for an A tbh

Reply 228

Simonium1010

7

Original post by Parallex

Me and my friend were saying it's an odd function so both are acceptable?

Exactly. Its because there is only one power of x, and it is an odd power. Both directions are the same. A simplidied example is: get a y=x^3 graph. Now make it y=-x^3... Is it a reflection in the x axis or y axis? You can't know unless I specify whether the minus sign is being cubed as well. But it doesn't matter cos y=x^3 flipped in either axis gives the same image, as the minus sign would stay a minus sign even if it were cubed.

Reply 229

marioman

8

Original post by Spriggs3

What do you guys think the raw mark for full UMS will be?

72.

Reply 230

Maprunner

Original post by Simonium1010

Exactly. Its because there is only one power of x, and it is an odd power. Both directions are the same. A simplidied example is: get a y=x^3 graph. Now make it y=-x^3... Is it a reflection in the x axis or y axis? You can't know unless I specify whether the minus sign is being cubed as well. But it doesn't matter cos y=x^3 flipped in either axis gives the same image, as the minus sign would stay a minus sign even if it were cubed.

This is why the question was 'describe A transformation', not 'describe THE transformation'

Reply 231

Sahil_

8

For the equation of the line question, is -6x + 8y +29 = 0 also right instead of
6x- 8y-29 =0

Reply 232

Rubberduckiller

2

Would u get Ecf if you work out a y co ordinate wrong then a answer using the wron points. Please help!!!

Reply 233

User10102929

1

Original post by Sahil_

For the equation of the line question, is -6x + 8y +29 = 0 also right instead of
6x- 8y-29 =0

yes, probably

Reply 234

marioman

8

Original post by Sahil_

For the equation of the line question, is -6x + 8y +29 = 0 also right instead of
6x- 8y-29 =0

Yes.

Reply 235

Parallex

6

FP1 tomorrow :biggrin:

Reply 236

Numpers123

A 62
b 56
my guess, so 90 ums I guess is 67
and 100 ums 72

Reply 237

c223

OP

2

Original post by Parallex

FP1 tomorrow :biggrin:

Was trying to forget about that one!

Reply 238

scrlk

7

Original post by Parallex

FP1 tomorrow :biggrin:

Good luck! :smile:

I thought it was an OK paper, maybe slightly harder than last year. Made a few really really stupid mistakes though...kicking myself!

From the OP:
June 2013: A - 60, B - 54, C - 48, D - 43, E - 38.
June 2014: A - 65, B - 59, C - 53, D - 47, E - 41.

So maybe A = 63 this year?