Year 12s: what will be the first way you research your future options? >>

Edexcel Core 3 - 21st June 2016 AM

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Reply 1580

jwanjwan

where the **** is arsey im having a meltdown

Reply 1581

Yua

Original post by mangoli

I used long division + factor theorum, although now i've seen it partial fractions would've been easier

Original post by Yua

did you remainder end up like so

4x+12

4(x+3)/(x+3)(x-2)

so 4/x-2

????

Reply 1582

Yua

Original post by Iamvery1/cos(c)

My sister just sat this exam and she realised afterwards that she completely missed out the last question because she didn't see it.

Will this be catastrophic if she wants a high A?

not if everything else was right

Reply 1583

Serine Soul

Original post by jwanjwan

where the **** is arsey im having a meltdown

He doesn't do model answers anymore

Reply 1584

Lolaturface

Original post by Yua

am i the only one that didn't use partial fractions?

Nope I just did it the core 3 way, divided, got a remainder, put that over the original fraction, factorised top and bottom and cancelled.

Reply 1585

buci98

Original post by blahblah21

Q1a, x=6, x=-5
b. a=6
2a. dy/dx = (20-4x^2)/(x^2+5)^2
b. x>rt(5) x<-rt(5)
3a. rt(5)cos(theta +26.57)
b. theta = 33.0, 273.9
c. theta = 86.1
4a. y=21, x=ln(2.5)
y=25 (k=25)
b. Proof
c. x1= 1.4368
x2= 1.4373
d. Show the change in sign. (gradient function)
5i. Turning points: 0.9463
ii. 0.5cosec(4y)
6a. A=3 B=4
b. x+2y-35=0 (or equivalent)
7a. arcsin(x) graph
b. x= -(2+rt(3))/2
8a. Proof
b. x= 0.294, -1.277, 1.865 and 1 more I think
9a. 6.740
b. Proof
c. T = 5ln(2+(2/e))

5 ii was 2cosec4y I think

Reply 1586

JLegion

Original post by mangoli

I used long division + factor theorum, although now i've seen it partial fractions would've been easier

To be fair long division is remarkably quick for this question in particular.

The remainder was nice and cancelled down into the form required beautifully.

Reply 1587

Michaelj99

Original post by Yua

am i the only one that didn't use partial fractions?

nope, i used polynomial division

Reply 1588

Josh Ironside

how many marks was Q9?

Reply 1589

TheBillPN

x4+x3−3x2+7x−6x2+x−6=x2+x−6

Anyone got the Algebraic Fraction method for me please?
I have never been taught long division, and I know I got the answers wrong, just looking to see if I got some method marks.

Reply 1590

Sophie Wilczek

Can anybody remember how much was question 1 a) worth?

Posted from TSR Mobile

Reply 1591

celecia01

Original post by Anon-

how did you show that it was the right root to 3 decimal places using an appropriate interval?

g(x) - (2(x)+43) with the appropriate x values will get you a change of sign

Reply 1592

khaleesi98

Original post by AhnafR

Guys which equation did you substitute in the values to get the sign change to prove x=1.473?

It was g(x) - (what g(x) was = to in that part)
So the one with the es minus the one that was ax+b...
That was probably useless sorry, but you might know what I mean? x

Reply 1593

edothero

b + b/e = [7.5/(15e^-1 + 15)]^-1

(be+b)/e = [7.5/(15e^-1 + 15)]^-1

be+b = [7.5/(15e^-1 + 15)]^-1 * e

b(e+1) = [7.5/(15e^-1 + 15)]^-1 * e

b = [7.5/(15e^-1 + 15)]^-1 * e / e + 1

b = 2

(This looks horrible but LaTeX doesn't seem to be working, sorry)

(edited 7 years ago)

Reply 1594

jshep000

Original post by Yua

did you remainder end up like so

4x+12

4(x+3)/(x+3)(x-2)

so 4/x-2

mate are we the same person? exactly what I did, long division, then my remainder cancelled it exactly like that you boss lad

Reply 1595

Josh Ironside

How Many Marks was Q9?

Reply 1596

Ainsleyy

Can anyone tell me what kind of time we could expect a 'model answers' unofficial mark scheme? Where they show all the working out etc? Are they normally on the day or the day after?

Reply 1597

sayshay

Original post by mpwb12345

Will send u it

Hi could you send it to me too please?

Reply 1598

cainy393

Original post by TheBillPN

Yeah ive seen the answers i want the method, i got it completely wrong as far as i can tell

Here is my working. I may have written the original question down wrong because I worked backwards from the answer to get the question. I'm fairly certain the first factor you had to take out was (x+3) but I could be wrong. Either way after I cancel that factor off top and bottom it is definitely correct.

Spoiler

(edited 7 years ago)

Reply 1599

username738914