AQA C2 June 2014 Unofficial Mark Scheme

I'm pretty sure the tan^2 question only gave you 3 values

Reply 181

Chloe<3

For the translation I put -10 not -2
How is it -2?

And btw hats off to u for storing all the answers in ur calculator, i run out of time just doing the papar let alone making note of my answers to help others haha

Reply 182

HesitantCicada

Original post by sadeqrahman

yeah, I got 2 values at the end, is that right?

tan^-1(sqrt(3/2) = 50.1

tan^-1(-sqrt(3/2) = -50.1 < +180 = 129.2

Surely these are the only solutions between 0 and 180?

Reply 183

bakedbeans247

20

Anyone know any sixth forms or sixth form colleges that will take a year 12 student to retake his AS-year and then do A2? Around London, like more near essex.

(edited 9 years ago)

Reply 184

HesitantCicada

Original post by Chloe<3

For the translation I put -10 not -2
How is it -2?

And btw hats off to u for storing all the answers in ur calculator, i run out of time just doing the papar let alone making note of my answers to help others haha

I didn't notice this trick in the exam either, but translating in the x-direction is f(x+k) it was something like 5(x-2) expands out to give the translation of 10.

Reply 185

OP

Original post by HesitantCicada

tan^-1(sqrt(3/2) = 50.1

tan^-1(-sqrt(3/2) = -50.1 < +180 = 129.2

Surely these are the only solutions between 0 and 180?

You are told

tan^2(2\theta) = \dfrac{3}{2}

, but if you square root that you get

tan(2\theta) = \pm\sqrt{\dfrac{3}{2}}

, which when you evaluate produces 4 answers in the correct range.

[br]tan(2\theta) = \pm\sqrt{\dfrac{3}{2}}[br]2\theta = 50.7, -50.7 \text{(working angles)}[br]2\theta \therefore = 50.7, 230.7, 129.3, 309.3[br]\theta \therefore = 25, 115, 65, 155[br]

Reply 186

I'm pretty sure the tan^2 question only gave you 3 values

Reply 187

HesitantCicada

Original post by Doomlar

You are told

tan^2(2\theta) = \dfrac{3}{2}

, but if you square root that you get

tan(2\theta) = \pm\sqrt{\dfrac{3}{2}}

, which when you evaluate produces 4 answers in the correct range.

[br]tan(2\theta) = \pm\sqrt{\dfrac{3}{2}}[br]2\theta = 50.7, -50.7 \text{(working angles)}[br]2\theta \therefore = 50.7, 230.7, 129.3, 309.3[br]\theta \therefore = 25, 115, 65, 155[br]

Are we certain it was tan(2x)? I must've missed that, I've scored 100UMS on every practice I've done and I've probably gotten an optimistic 64 marks on this... Lucky me.

Reply 188

Ellios

14

Couple of questions
Would I drop a mark for leaving out the +C on the integration? As I know that sometimes it's not required on the mark scheme
Also I guessed that q=3 and wrote that down a log with a load of working that didn't get me to the answer
Will I get a mark for the answer even though it's just guessed?

Posted from TSR Mobile

Reply 189

I'm pretty sure the tan<2 question only gave you 3 values

Reply 190

AstusUK

For the area of the integral, I don't see how it was 49/10. I can't remember what wrote in the exam but i recalculated it and got 31/6. You get 1 + 2 + 2/3 + 3/2 = 31/6.

Reply 191

OP

Original post by Ellios

Couple of questions
Would I drop a mark for leaving out the +C on the integration? As I know that sometimes it's not required on the mark scheme
Also I guessed that q=3 and wrote that down a log with a load of working that didn't get me to the answer
Will I get a mark for the answer even though it's just guessed?

Posted from TSR Mobile

To answer your first question, it really depends how everyone else did; if everyone did well on that question and put +c then they will require +c, otherwise yeah you may get the mark.

I'm not sure for your second question; sometimes they say you have to have a correct method but who knows :/

Reply 192

pryngles

9

Original post by Ellios

Couple of questions
Would I drop a mark for leaving out the +C on the integration? As I know that sometimes it's not required on the mark scheme
Also I guessed that q=3 and wrote that down a log with a load of working that didn't get me to the answer
Will I get a mark for the answer even though it's just guessed?

Posted from TSR Mobile

I doubt that you would get the A1 mark as the mark schemes usually request the full equation plus the q= for questions like these for the A1 mark

Reply 193

I'm pretty sure the tan2 question only gave you 3 values

Reply 194

OP

Original post by BlackLipBastard

I'm pretty sure the tan^2 question only gave you 3 values

Original post by BlackLipBastard

I'm pretty sure the tan^2 question only gave you 3 values

Original post by BlackLipBastard

I'm pretty sure the tan<2 question only gave you 3 values

Original post by BlackLipBastard

I'm pretty sure the tan2 question only gave you 3 values

See:

Original post by Doomlar

You are told

tan^2(2\theta) = \dfrac{3}{2}

, but if you square root that you get

tan(2\theta) = \pm\sqrt{\dfrac{3}{2}}

, which when you evaluate produces 4 answers in the correct range.

[br]tan(2\theta) = \pm\sqrt{\dfrac{3}{2}}[br]2\theta = 50.7, -50.7 \text{(working angles)}[br]2\theta \therefore = 50.7, 230.7, 129.3, 309.3[br]\theta \therefore = 25, 115, 65, 155[br]

Reply 195

Original post by HesitantCicada

tan^-1(sqrt(3/2) = 50.1

tan^-1(-sqrt(3/2) = -50.1 < +180 = 129.2

Surely these are the only solutions between 0 and 180?

Nah if you noticed, in the equation where it said hence, it was slightly different to the original. It had a 2 so for your working out you would times the 180 to give you 360, work out the values and then divide by 2 at the end

Reply 196

rockon8912

2

Does anyone remember what the actual questions for 2bi and 9c were?

Reply 197

TSR repeating my posts smh

Reply 198

OP