Results 1 to 4 of 4

Math Help - Binomial expansion questions

  1. #1
    Member
    Joined
    Oct 2008
    Posts
    157

    Binomial expansion questions

    I think I did this well but I'd like them checked so I know I have the right answers. Could you please look at these for me?

    1] (1 + 2x)^6
    = 1 + 12x + 60x^2 + 160x^3 + 240x^4 + 96x^5 + 64x^6

    2] (3 + 2x)^5
    = 243 + 810x + 1080x^2 + 730x^3 + 240x^4 + 32x^5

    3] (5 + 3x)^3
    = 125 + 225x + 135x^2 + 27x^3

    4] (4 - 2x)^4
    = 256 - 512x + 384x^2 - 108x^3 + 16x^4

    Thanks if you can help with this!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Newbie
    Joined
    Mar 2009
    Posts
    11
    Quote Originally Posted by db5vry View Post
    I think I did this well but I'd like them checked so I know I have the right answers. Could you please look at these for me?

    1] (1 + 2x)^6
    = 1 + 12x + 60x^2 + 160x^3 + 240x^4 + 96x^5 + 64x^6

    2] (3 + 2x)^5
    = 243 + 810x + 1080x^2 + 730x^3 + 240x^4 + 32x^5

    3] (5 + 3x)^3
    = 125 + 225x + 135x^2 + 27x^3

    4] (4 - 2x)^4
    = 256 - 512x + 384x^2 - 108x^3 + 16x^4

    Thanks if you can help with this!
    1, 2, 4 are not correct.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Oct 2008
    Posts
    157
    Quote Originally Posted by niranjan View Post
    1, 2, 4 are not correct.
    Okay I made a mistake with a coefficient in the first one - I saw that and corrected it, but I worked out 2 and 4 again:

    2]  (3 + 2x)^5
    =  125 + 10x + 40x^2 + 80x^3 + 80x^4 + 32x^5

    4]  (4 - 2x)^4
    =  256 - 8x + 24x^2 - 48x^3 + 16x^4

    Are these right now?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Newbie
    Joined
    Mar 2009
    Posts
    11
    Quote Originally Posted by db5vry View Post
    Okay I made a mistake with a coefficient in the first one - I saw that and corrected it, but I worked out 2 and 4 again:

    2]  (3 + 2x)^5
    =  125 + 10x + 40x^2 + 80x^3 + 80x^4 + 32x^5

    4]  (4 - 2x)^4
    =  256 - 8x + 24x^2 - 48x^3 + 16x^4

    Are these right now?
    2]  (3 + 2x)^5
    =  243 + 810x + 1080x^2 + 720x^3 + 240x^4 + 32x^5

    4]  (4 - 2x)^4
    =  256 - 512x + 384x^2 - 128x^3 + 16x^4
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 6
    Last Post: May 1st 2009, 12:37 PM
  2. Unusual Binomial Expansion Questions
    Posted in the Algebra Forum
    Replies: 1
    Last Post: April 3rd 2009, 11:59 AM
  3. Binomial expansion
    Posted in the Algebra Forum
    Replies: 3
    Last Post: March 3rd 2009, 09:42 AM
  4. Binomial Expansion
    Posted in the Algebra Forum
    Replies: 16
    Last Post: July 24th 2008, 03:01 PM
  5. binomial expansion
    Posted in the Calculus Forum
    Replies: 4
    Last Post: February 24th 2008, 10:50 AM

Search Tags


/mathhelpforum @mathhelpforum