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# bionomial help please small question watch

1. hey math peeps
I've got a small question
for example
use expansion for (3+10x)^4 with an appropriate value of x to find the exact value of *1003)^ stating the value of x you have used
ok I can solve everything in this question but the only problem is that I don't know how to obtain a vlue for x to continue solving the question ...if anybody can be kind enough to just explain how to find x
2. 1003 sounds large for these types of questions
3. (Original post by elpaw)
1003 sounds large for these types of questions
it's on p2 review excercises 1
4. have you done the binomial expansion?
you should get: 81 + 1080x + 5400x^2 + 12000x^3 + 10000x^4

you want to find (1003)^4, and you have the expansion for (3+10x)^4, so:

3+10x = 1003
x = 100

Sub, x=100 into the expansion, and you'll get a very large number (namely 1012054108081 )
5. *sloaps forehead* doh, here was me thinking x <= 10/3 for convergence.
6. hehe, it's easier having the question in front of you
i was kinda lost when i was reading what she typed....
7. (Original post by mockel)
have you done the binomial expansion?
you should get: 81 + 1080x + 5400x^2 + 12000x^3 + 10000x^4

you want to find (1003)^4, and you have the expansion for (3+10x)^4, so:

3+10x = 1003
x = 100

Sub, x=100 into the expansion, and you'll get a very large number (namely 1012054108081 )
Bless ya mockel bockel ,just stupid me wanted that.yep I made the expansion
8. Its in the Edexcel P2 book, pg 85, Review Exercise 1, question 3...

Thats what that means.
9. (Original post by mockel)
hehe, it's easier having the question in front of you
i was kinda lost when i was reading what she typed....
why I wrote exactly what was written in my book, Blame p2
10. (Original post by habosh)
why I wrote exactly what was written in my book, Blame p2
you wrote something with a star and 1003 raised to the power of nothing (not zero, but there actually wasn't anything there!).....i didn't know what was going on!
11. (Original post by mockel)
you wrote something with a star and 1003 raised to the power of nothing (not zero, but there actually wasn't anything there!).....i didn't know what was going on!
oops my fault was rasied to the power 4 I just messed typing..sorry.don't blame p2 then
12. now, maybe you can understand why poor elpaw was left in the dark
13. (Original post by mockel)
now, maybe you can understand why poor elpaw was left in the dark
poor elpaw
eplaw I'm so sorry hun forgive me
14. tis not your fault, i was overcomplicating it. i was thinking of the binomial expansion to the power n where n is negative or real. so x would have to be less than 10/3 for convergence. but this was a simpler case. (and x can be any number)
15. love it but there not questions!!!!!!!!!!1

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