Results 1 to 2 of 2

Math Help - How do I simplify this expression?

  1. #1
    Newbie
    Joined
    Jan 2009
    Posts
    5

    Post How do I simplify this expression?




    250X^9y^5 all inside a 3rd root thing...
    The answer is 5X^3 Y^3 and then a "2y^2" which is inside a square root thing.
    Thanks a lot!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor

    Joined
    Apr 2005
    Posts
    16,444
    Thanks
    1863
    Quote Originally Posted by hersheybar11 View Post



    250X^9y^5 all inside a 3rd root thing...
    The answer is 5X^3 Y^3 and then a "2y^2" which is inside a square root thing.
    Thanks a lot!
    \sqrt[3]{250 x^9 y^5}

    Since that is a cube root, set everything into cubes as much as possible.

    250= 125* 2 and 125= 5*5*5= 5^3

    x^9= (x*x*x)(x*x*x)(x*x*x)= (x^3)^3

    y^5= y*y*y*y*y= (y*y)(y*y*y)= y^2 y^3

    So what that is is \sqrt[3]{2(5^3)(x^3)^3y^2y^3}
    Of course, the definition of "cube root" is that \sqrt[3]{a^3}= a.

    \sqrt[3]{250 x^9 y^5}= \sqrt[3]{2}\sqrt[3]{5^3}\sqrt[3]{(x^3)^3}\sqrt[3]{y^2}\sqrt[3]{y^3}

    = \sqrt[3]{2}(5)(x^3)\sqrt[3]{y^2}y= 5x^3y\sqrt[3]{2y^2}
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Simplify this expression...
    Posted in the Algebra Forum
    Replies: 5
    Last Post: March 6th 2011, 01:05 PM
  2. help to simplify this expression
    Posted in the Calculus Forum
    Replies: 0
    Last Post: July 26th 2010, 02:05 AM
  3. Simplify the expression
    Posted in the Algebra Forum
    Replies: 1
    Last Post: September 8th 2009, 05:31 AM
  4. Simplify Expression for y
    Posted in the Algebra Forum
    Replies: 7
    Last Post: August 25th 2009, 02:49 PM
  5. Simplify the expression
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: February 24th 2008, 07:50 PM

Search Tags


/mathhelpforum @mathhelpforum