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# C4 Binomial Expansion watch

1. (Original post by Student403)
I appreciate the compliment but neither am I

Zacken
you think too highly of me.
2. (Original post by Zacken)
Don't listen to that. It's wrong. The binomial expansion for non-natural powers is only valid for . (that is the power series converges in this radius), now map and the same condition states that .

Indeed, thank you for pointing that out. I really wish some people wouldn't blurt out what they say without knowing anything about it.
Thank you for clearing that up!
3. (Original post by Dinaa)
I'm not the brightest sooo

Student403
**** Diamonds

What lig1729 said is correct, it's to ensure the series converges.

You know when we were going through the values for which the expansion is valid in chapter 3, they've basically replaced |x| < 1 with, |-2/x| < 1 and that rearranges to |x| > 2
4. (Original post by Zacken)
you think too highly of me.
It's justified
5. (Original post by npstudent)
...
By the way, I've moved this to the maths forum for you! Next time you have a maths question, it'd be better to post it there, you'll get more relevant help far quicker.
6. (Original post by Zacken)
By the way, I've moved this to the maths forum for you! Next time you have a maths question, it'd be better to post it there, you'll get more relevant help far quicker.
Thanks, will do
7. (Original post by **** Diamonds)
What lig1729 said is correct, it's to ensure the series converges.

You know when we were going through the values for which the expansion is valid in chapter 3, they've basically replaced |x| < 1 with, |-2/x| < 1 and that rearranges to |x| > 2
gtcha
8. (Original post by Dinaa)
Woah that was a tad harsh
And so it should be. It's pretty obvious it is a convergence criterion but even if you don't know that you shouldn't type misleading nonsense.
9. (Original post by lig1729)
And so it should be. It's pretty obvious it is a convergence criterion but even if you don't know that you shouldn't type misleading nonsense.
I learnt something

sorry OP
10. (Original post by Zacken)
By the way, I've moved this to the maths forum for you! Next time you have a maths question, it'd be better to post it there, you'll get more relevant help far quicker.
One more question, how would I get it to be in descending powers of x?
11. (Original post by npstudent)
One more question, how would I get it to be in descending powers of x?
Write the terms down the opposite way than you calculate them.
12. (Original post by npstudent)
One more question, how would I get it to be in descending powers of x?
You just do it the normal way and then go up to the term in x^4 or whatever the highest they ask you for. e.g: 1 + x + x^2 + x^3 + ... (not yours, just an example)

then descending order you just write it the other way so

... + x^3 + x^2 + x + 1, apply this to your case.
13. (Original post by npstudent)
Thank you for clearing that up!

i have a question that i dont know how to do

BTW -(2) means squared
(3) means cubed

sorry i dont know what type of question ths is, thanks in advance

(3a(2) +3ab+36(2)
/ 4a+4b)

x

2a(2)-2b(2)
/9a(3)-9b(3)
14. (Original post by I.sarkar)

i have a question that i dont know how to do

BTW -(2) means squared
(3) means cubed

sorry i dont know what type of question ths is, thanks in advance

(3a(2) +3ab+36(2)
/ 4a+4b)

x

2a(2)-2b(2)
/9a(3)-9b(3)
wouldn't be easier to post a photo of the question and your workings?
15. (Original post by I.sarkar)
...
16. (Original post by Zacken)
I think he might come under the "you can lead 'em to water but you can't make 'em drink" school of poster.
17. why has everyone started core 4 whiltst were doing stats now?
18. (Original post by TeeEm)
wouldn't be easier to post a photo of the question and your workings?
sorry about that, iknow it would be logical but for some reason my *****y phone wont connct to the computer
19. (Original post by I.sarkar)
sorry about that, iknow it would be logical but for some reason my *****y phone wont connct to the computer
I thought you were on a laptop or a computer

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