You are Here: Home >< Maths

# nth term of a sequence.... Watch

1. 
2. Set , and consider that . You should be able to make some progress from there (unless I've made a misunderstanding somewhere).
3. Yeah that sounds right.
4. 
5. (Original post by flown_muse)
Okay, now I have:

and now I have an issue, because I can't find a value of k that can make both the top and the bottom equal to a power of 4.

I'm clearly doing something wrong
Write it as , and remember that , so you can expand the powers to get something easier.
6. (Original post by flown_muse)
Okay, now I have:

and now I have an issue, because I can't find a value of k that can make both the top and the bottom equal to a power of 4.

I'm clearly doing something wrong
Expand the numerator and simplify.
7. 
8. (Original post by flown_muse)

etc.?
What's 3--1?

Apart from that yeah that's right. You can get rid of the 1 btw.
Yeah that's right. You can get rid of the 1 btw.
So, I have ended up with:

Therefore,
10. (Original post by flown_muse)
So, I have ended up with:

Therefore,
Hang on, where did the last line come from?
Hang on, where did the last line come from?
Because the question wants me to find An in terms of powers of 4, so I'm setting the power equal to 4.

(I think?)
12. Oh. I never thought of that. I think you are right, because otherwise I end up with n=0 and the answer is just a number with no powers. Argh! Thanks
13. (Original post by flown_muse)
Oh. I never thought of that. I think you are right, because otherwise I end up with n=0 and the answer is just a number with no powers. Argh! Thanks
Yeah you need to re-write it . In terms of 4^ something, since this would then imply powers of 4.

Updated: March 18, 2012
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Today on TSR

### HELP!

Mum wants to come to Freshers

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams

## Groups associated with this forum:

View associated groups
Study resources

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.