Edexcel A2 C4 Mathematics June 2016 - Official Thread

Reply 3020

yesyesyesno

3

sorry guys this is what I meant lol

Reply 3021

Zacken

22

Original post by metrize

Oh so are both correct, but you just get a different constant c?

Yep, my mistake.

Reply 3022

k.russell

13

@smackitintheair
IMG_0317[1].jpg

Attachment not found

that's how you do part 1, hopefully you can do the rest yourself :smile:

IMG_0318[1].jpg509.7KB

Reply 3023

alvosm

7

anyone knows which are the hardest c4 papers? is it better to do solomon and elmwood rather than the normal past papers? also is it worth it doing the review exercises?

thanks :smile:

Reply 3024

math42

20

Original post by alvosm

anyone knows which are the hardest c4 papers? is it better to do solomon and elmwood rather than the normal past papers? also is it worth it doing the review exercises?

thanks :smile:

No, but if you check old grade boundaries, you can find them. It is better to do Edexcel papers, for sure. If you run out, madasmaths has probably the best non-edexcel practice papers

Reply 3025

Student7th

1

Original post by metrize

Oh so are both correct, but you just get a different constant c?

Yes, that's the case. It seems confusing at first but now i get why it makes sense

Reply 3026

lordoftheties

13

How do you do part b?
Screen Shot 2016-06-19 at 20.18.57.png

Reply 3027

math42

20

Original post by lordoftheties

How do you do part b?
Screen Shot 2016-06-19 at 20.18.57.png

In general for range questions you look at any turning points, and at endpoints (or behaviour at infinity/minus infinity if there isn't an endpoint).

Reply 3028

XxKingSniprxX

21

If I come out of C3+C4 with 95% ums each and get my A* ---> :woohoo:

Then I know my hard work paid off. :h:

I hope C4 vector question is simple + nothing nasty on the trig functions/stupid hippy "find range" questions
come up.

(edited 7 years ago)

Reply 3029

yesyesyesno

3

Original post by XxKingSniprxX

If I come out of C3+C4 with 95% ums each and get my A* ---> :woohoo:

Then I know my hard work paid off. :h:

:

I hope C4 vector question is simple + nothing nasty on the trig functions/stupid hippy "find range" questions
come up.

Last year's vectors were straightforward and so were the year before so we'll probably get some difficult vectors.

Also what's so difficult about range questions :tongue:

Reply 3030

XxKingSniprxX

21

Original post by yesyesyesno

Last year's vectors were straightforward and so were the year before so we'll probably get some difficult vectors.

Also what's so difficult about range questions :tongue:

I know... just hope I draw a clear diagram & things work out well. The range questions are the only place I drop marks in C3 and its been the case for god knows how many past papers I've done. #oldhabitsdiehard :argh:

Reply 3031

RetroSpectro

2

The population in thousands, P, of a town at time t years after 1st January 1980 is modelled by the formula
P = 30 + 50e^0.002t

- use this model to estimate the year in which the population first exceeds 84 000

The mark scheme doesn't seem to agree with my answer can I double check with someone

Reply 3032

Craig1998

12

Original post by RetroSpectro

The population in thousands, P, of a town at time t years after 1st January 1980 is modelled by the formula
P = 30 + 50e^0.002t

- use this model to estimate the year in which the population first exceeds 84 000

The mark scheme doesn't seem to agree with my answer can I double check with someone

1984.

Reply 3033

RetroSpectro

2

Original post by Craig1998

1984.

Thats not what i got, and neither is that in the mark scheme

Reply 3034

Craig1998

12

Original post by RetroSpectro

Thats not what i got, and neither is that in the mark scheme

Oml I'm so stupid :biggrin:

NVM just seen it's 0.002

Reply 3035

Craig1998

12

Original post by RetroSpectro

Thats not what i got, and neither is that in the mark scheme

2009.

Reply 3036

RetroSpectro

2

Original post by Craig1998

2009.

I think you're going wrong somewhere, thats not it either :K:

Reply 3037

yesyesyesno

3

Original post by RetroSpectro

The population in thousands, P, of a town at time t years after 1st January 1980 is modelled by the formula
P = 30 + 50e^0.002t

- use this model to estimate the year in which the population first exceeds 84 000

The mark scheme doesn't seem to agree with my answer can I double check with someone

I've done it really quickly in scribbles but is it 2019? *

(edited 7 years ago)

Reply 3038

Craig1998

12

Original post by RetroSpectro

I think you're going wrong somewhere, thats not it either :K:

30+50e^0.002t> 84
50e^0.002t>54
e^0.002t>27/25
t/500>ln1.08
t>500ln1.08
t>38.4

Therefore t = 39
Therefore year = 1980+39
= 2019.

Oh god I'm failing c4. :frown: