# Edexcel A2 C3 Mathematics 12th June 2015Watch

This discussion is closed.
3 years ago
#1401
June 2014 4c???
Find the gradient of the line using change in y/change in x which is 12/6. This means the gradient and thus a is 2. Now sub in given x and y values to find b.

Posted from TSR Mobile
0
3 years ago
#1402
(Original post by dnpnstn)
you know g(x)=ln2x, so for g(x^2), it must be ln2x^2. You do the same with g(x^3)

This gives you:
ln2x + ln2x^2 + ln2x^3 = 6
You can then split this up using rules of logs
(lnx +ln2) + (lnx^2 + ln2) + (lnx^3 + ln2) =6
Bring down the powers of x and simplify, giving
6lnx + 3ln2 = 6
Then just solve for x
Thank you so much! I wasnt sure of the last two steps!
0
3 years ago
#1403
Thanks!!! Do i just take the mod value to be positive? i mean i did origianally but then i thought should i have done it negative as well?
mod value is always positive
0
3 years ago
#1404
so basically Solomon papers are from A to L is it that the closer it is to L the harder it gets?
0
3 years ago
#1405
(Original post by laurenjjj)
g(x)=ln2(x)
g(x)+g(x^2)+g(x^3)=6
when x=x ---> g(x)=ln2(x) ---> expand the brackets ---> ln2x
when x=x^2 ---> g(x^2)=ln2(x^2) ---> expand the brackets ---> ln2x^2
when x=x^3 ---> g(x^3)=ln2(x^3) ---> expand the brackets ---> ln2x^3

ln2x + ln2x^2 + ln2x^3 = 6
ln((2x) x (2x^2) x (2x^3)) = 6
ln(8x^6) = 6
8x^6 = e^6
x^6 = (e^6)/8
x= the sixth root of e^6/8

made it as clear as i can, hope this helps
0
3 years ago
#1406
so lnx differentiates to 1/x
does any lnx differentiate to 1/x as in ln2x, ln3x etc.?
0
3 years ago
#1407
(Original post by TeeEm)
year 2044
Can I know what question and past paper that is from please?
0
3 years ago
#1408
(Original post by beckm)
so lnx differentiates to 1/x
does any lnx differentiate to 1/x as in ln2x, ln3x etc.?
Yes. Apply the chain rule and you'll see why
0
3 years ago
#1409
(Original post by Seventeen)
so basically Solomon papers are from A to L is it that the closer it is to L the harder it gets?
don't think so, pretty sure they are roughly all as hard as each other
0
3 years ago
#1410
(Original post by beckm)
so lnx differentiates to 1/x
does any lnx differentiate to 1/x as in ln2x, ln3x etc.?
ln2x differentiates to 2/2x which simplifies to 1/x
0
3 years ago
#1411
(Original post by Gilo98)
Yes. Apply the chain rule and you'll see why
but if its like 2lnx then its 2/x?
0
3 years ago
#1412
(Original post by beckm)
but if its like 2lnx then its 2/x?
Yep
0
3 years ago
#1413
(Original post by rache11ouise)
ln2x differentiates to 2/2x which simplifies to 1/x
right ok thank you
0
3 years ago
#1414
(Original post by Gilo98)
Yep
fab thank you
0
3 years ago
#1415
Anyone? Hardest C3 paper (not including June 13) dont have much time to do alot of papers. Can only do 1/2

Posted from TSR Mobile
0
3 years ago
#1416
Basically ln(u) wher u is function of x 1/u du/dx
Apply that everywhere. Simple application of chain rule.

Posted from TSR Mobile
0
3 years ago
#1417
(Original post by physicsmaths)
Anyone? Hardest C3 paper (not including June 13) dont have much time to do alot of papers. Can only do 1/2

Posted from TSR Mobile
June 2014 had slightly low boundaries. Papers have been fairly consistent otherwise. Maybe look at recent IAL papers.
0
3 years ago
#1418
(Original post by physicsmaths)
Anyone? Hardest C3 paper (not including June 13) dont have much time to do alot of papers. Can only do 1/2

Posted from TSR Mobile
^^ what he said! ... Was just going to ask this
0
3 years ago
#1419
(Original post by sagar448)
Can I know what question and past paper that is from please?
year?
I just wrote it a few hours ago
0
3 years ago
#1420
look at solomon tiered papers they are set on difficultly, gold being the hardest

http://www.physicsandmathstutor.com/...e-silver-gold/
0
X
new posts
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### University open days

• Cranfield University
Cranfield Forensic MSc Programme Open Day Postgraduate
Thu, 25 Apr '19
• University of the Arts London
Open day: MA Footwear and MA Fashion Artefact Postgraduate
Thu, 25 Apr '19
• Cardiff Metropolitan University
Sat, 27 Apr '19

### Poll

Join the discussion

#### Have you registered to vote?

Yes! (26)
50%
No - but I will (1)
1.92%
No - I don't want to (1)
1.92%
No - I can't vote (<18, not in UK, etc) (24)
46.15%