Results 1 to 10 of 10

Math Help - 1 + 3 squareroot 5

  1. #1
    Senior Member
    Joined
    Apr 2006
    Posts
    290

    1 + 3 squareroot 5

    (1 + 3squareroot of 5)squared = p + qsquareroot of 5 where p and q are integers.

    What are the values of p and q?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Natasha1 View Post
    (1 + 3squareroot of 5)squared = p + qsquareroot of 5 where p and q are integers.

    What are the values of p and q?
    (1 + 3 \sqrt{5})^2 = p + q\sqrt{5}.

    Expand the left hand side and match it with the bits you have on the right hand side.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor Also sprach Zarathustra's Avatar
    Joined
    Dec 2009
    From
    Russia
    Posts
    1,506
    Thanks
    1
    Quote Originally Posted by Natasha1 View Post
    (1 + 3squareroot of 5)squared = p + qsquareroot of 5 where p and q are integers.

    What are the values of p and q?
    Calculate (1 + 3squareroot of 5)squared
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Senior Member
    Joined
    Apr 2006
    Posts
    290
    what is 2 x 3squareroot of 5?

    Should it be treated like (a+b)squared?

    asquared + bsquared + 2ab
    Last edited by mr fantastic; October 25th 2010 at 01:05 PM. Reason: Merged posts
    Follow Math Help Forum on Facebook and Google+

  5. #5
    MHF Contributor Also sprach Zarathustra's Avatar
    Joined
    Dec 2009
    From
    Russia
    Posts
    1,506
    Thanks
    1
    Quote Originally Posted by Natasha1 View Post
    Should it be treated like (a+b)squared?
    Indeed.
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Senior Member
    Joined
    Apr 2006
    Posts
    290
    right right... then lets see, is it

    1 + 45 + 6squareroot of 10 = p + qsquareroot of 5
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Natasha1 View Post
    right right... then lets see, is it

    1 + 45 + 6squareroot of 10 = p + qsquareroot of 5
    Yes. And 1 + 45 = 46. Now compare each side.
    Follow Math Help Forum on Facebook and Google+

  8. #8
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    Quote Originally Posted by Natasha1 View Post
    right right... then lets see, is it

    1 + 45 + 6squareroot of 10 = p + qsquareroot of 5


    Hi Natasha1,

    It is 46+6\sqrt{5}

    The 2 is multiplied by the coefficient of the radical, not what's inside.

    2ab=2(1)(3\sqrt{5})=6\sqrt{5}

    Last edited by masters; October 26th 2010 at 05:04 AM.
    Follow Math Help Forum on Facebook and Google+

  9. #9
    Senior Member
    Joined
    Apr 2006
    Posts
    290
    so p = 46 and q = 6 but the squareroots are both different? We have a 10 and a 5?
    Follow Math Help Forum on Facebook and Google+

  10. #10
    Senior Member
    Joined
    Apr 2006
    Posts
    290
    Oh so it's 46 + 6squareroot of 5 = p + qsquareroot of 5.

    Thanks a million gents!!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Approximating Squareroot
    Posted in the Calculus Forum
    Replies: 3
    Last Post: April 27th 2010, 12:15 PM
  2. Derivative of Squareroot
    Posted in the Calculus Forum
    Replies: 4
    Last Post: December 31st 2009, 12:28 PM
  3. squareroot (1 + ...) , log (1 + ...)
    Posted in the Calculus Forum
    Replies: 2
    Last Post: August 11th 2009, 04:21 PM
  4. squareroot (1 + ...) , log (1 + ...)
    Posted in the Calculus Forum
    Replies: 1
    Last Post: August 11th 2009, 01:50 PM
  5. integral (w^5)(squareroot((w^3)-1)
    Posted in the Calculus Forum
    Replies: 2
    Last Post: June 7th 2008, 11:35 AM

Search Tags


/mathhelpforum @mathhelpforum