A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 5 years ago

the sum of the series 20c0 - 20c1 + 20c2 - 20c3+........+20c10 is

  • This Question is Closed
  1. amistre64
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    20(c0-c1+c2-c3 + ... + c10); what are the coeefs?

  2. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i think it should use binomial form (1-x)^20 or somewhat like it...

  3. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    no no no hold on.. its a combinatorics problem. the 'c' here means that

  4. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    use (1-x)^20+(1+x)^20 you will get the ans...

  5. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    deeprony have u understood the p problem??????

  6. amistre64
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    20!/20! - 20!/19! + 20!/18!2! .... like that?

  7. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    "(1-x)^20+(1+x)^20" what is x here?? yea i understood that quetion=)

  8. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yes mistre thats correct

  9. amistre64
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i stil gotta do these the brute force way ;)

  10. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    isint there a formula??

  11. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    (1-x)^20=20c0-20c1x+.......... now 20cn=20c20-n. and thus 20c20=20c0. and so on put x=1. 20c0-20c1+.....=0 2(20c0-20c1-.......+20c10)-20c10=0 hence ans is (20c10)/2

  12. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    can you explain what you did hre.. 20c0-20c1+.....=0 2(20c0-20c1-.......+20c10)-20c10=0

  13. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i put just x=1 in the 1st expansion of (1-x)^20

  14. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yea ok wat did u do thn??

  15. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    that is the way of doing.....using a binomial series....

  16. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i had (1-x)^20=20c0-20c1x+20c2x^2.... put x=1 0=20c0-20c1+20c2......

  17. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    use 20c20=20c0,20c19=20c1,.......20c11=20c9.

  18. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    i got that olryt... i didnt understnd what u did xt

  19. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    *nxt

  20. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    you get the term 20c0,20c1,....20c9 twice but 20c10 only one...

  21. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ahh i c... got it now...=))

  22. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    thus i write .. 0=2(20c0-20c1+20c2........+20c10)-20c10

  23. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    okkkkkkkkkkkkkkkkkk?????????

  24. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yea!

  25. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    these are some tricks to do it...............

  26. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    is the answer 0

  27. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.