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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

Hi;

I did not work on it. What did you do?

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**zetafunc.****Guest**

I wrote it out as a product of 3 series and then looked at the different ways of making x^66. There is a nice pattern so it only takes a couple of minutes.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

You used a binomial expansion for each one?

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**zetafunc.****Guest**

No, only for (1 - x^6)^(-2). The other two products are simple geometric series so you can use the same method you described to get the co-efficients.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

Luckily they are only asking for small numbers.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**zetafunc.****Guest**

It should still be OK no matter what co-efficient they asked for -- there is a nice pattern.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

Yes, I am getting 1,1,1,2,2,2,5,5,5,8,8,8,14,14,14...

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

Hmm, I didn't notice that... still, I am really surprised this question is in STEP II, it seems almost a giveaway!

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

Sorry, nothing to do with the tribonacci numbers.

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

What do you think of the other questions?

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

I thought it was generally pretty tough. Not the kind of questions that come quickly.

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

Yes, some questions in STEP do take a while to get started on. Generally they set Q1 to be a question that everyone can at least attempt without much advanced knowledge... the grade boundaries for this paper were:

S - 91/120

1 - 72/120

2 - 60/120

3 - 31/120

where each question is worth 20 marks (if you answer more than six, they pick your highest-scoring).

Generally, a good rule of thumb is that 4 full solutions is always a solid 1 (except for in 2010), although it's probably better to attempt a couple more just in case you made some mistakes in them.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

You will be taking the 2013 soon?

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

Yeah, STEP II is in 13 days. I am more worried about STEP III, that has always been my weakest one...

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

When you do well with the STEP II and III what advantage will you get?

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

None -- just the grade. Normally, if people have a Cambridge offer, then they just have to get 1,1 in STEP II and III (or in F's case she only had to get 1,2 because she came from a (my) state school that doesn't offer any support with STEP).

Technically none of my exams matter anymore because I already have the grades to go to UCL... so there is a lot less pressure here.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

Let me take a look at the Step III paper for 2012.

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

OK but do not tell me anything about it. F said it was very hard and there were 4 questions with sums to infinity, and that the first question had an error in it...

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

Do not worry, I might not get any of them!

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

It's that difficult?!

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

Maybe 1 - 4 can be worked on quickly. There is a product in there and a sum that may or may not be easy, I do not know.

There is a sketching problem that probably can be done.

The probability ones might be 50 - 50.

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

Thanks. I really want to do this paper and get a 1 -- that would give me lots of confidence after STEP III 2011!

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

Hopefully, you will do better than I am thinking I would do there.

**In mathematics, you don't understand things. You just get used to them.**

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**zetafunc.****Guest**

I am surprised that around 12% got an S in that paper last year. For some reason, STEP III always has the highest proportion of S-grades compared to STEP II and I.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 88,998

There are 2 DE's on this one. F can handle them?

**In mathematics, you don't understand things. You just get used to them.**

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