You are Here: Home

Binomial Expansion HELP! watch

1. Can anyone help me with this?
Attached Images

2. The binomial theorem says that (1+x)^n = 1 + nx + n(n-1)(x^2)/2! +
n(n-1)(n-2)(x^3)/3! + ...
So replace n with b and x with (ax) and then you should be able to see what to do from there.
3. What was the answer, I got a=24/11 and b=11/2 which I doubt
4. I had another go and only considered the coefficients and squared the a and managed to get more feasible results. I got a=15/2 and b=8/5.

Oh, when I expand it using those values my x^2 value is wrong since I get 27 and not 54 so still not right.
5. (Original post by BinaryJava)
I had another go and only considered the coefficients and squared the a and managed to get more feasible results. I got a=15/2 and b=8/5.

Oh, when I expand it using those values my x^2 value is wrong since I get 27 and not 54 so still not right.
You should get a=3 and b=4
6. (Original post by B_9710)
You should get a=3 and b=4
Yep I have managed to get that now, my 2! was getting mixed up somewhere. I guess that is what I get for doing maths at 2 AM XD
7. (Original post by b_9710)
you should get a=3 and b=4
thank you so much

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:
Updated: September 13, 2015
Today on TSR

Thought he was 19... really he's 14

University open days

Wed, 25 Jul '18
2. University of Buckingham
Wed, 25 Jul '18
3. Bournemouth University