Results 1 to 6 of 6

Math Help - Simplifying fractions with exponents

  1. #1
    Newbie
    Joined
    Apr 2009
    Posts
    2

    Simplifying fractions with exponents

    I have to simplify this and im totally confused step by step help would be so much appreciated!
    <br />
\left( \frac {-6x^2y}{2xy^3} \right)^3<br />
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor Reckoner's Avatar
    Joined
    May 2008
    From
    Baltimore, MD (USA)
    Posts
    1,024
    Thanks
    75
    Awards
    1

    Smile

    Quote Originally Posted by HeidiHectic View Post
    I have to simplify this and im totally confused step by step help would be so much appreciated!
    <br />
\left( \frac {-6x^2y}{2xy^3} \right)^3<br />
    Have you made any attempt at the problem? You should be familiar with these properties of exponentiation:

    (ab)^n=a^nb^n

    \left(\frac ab\right)^n=\frac{a^n}{b^n}

    a^{-n}=\frac1{a^n}

    a^ma^n=a^{m+n}

    \frac{a^m}{a^n}=a^{m-n}

    (where a,\,b,\,m and n have values such that the above expressions are defined)

    Note that a variable without an exponent can be thought of as being raised to the 1st power.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Apr 2009
    Posts
    2
    yes, i understand those im just not sure what to do after you distribute the exponent.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor Reckoner's Avatar
    Joined
    May 2008
    From
    Baltimore, MD (USA)
    Posts
    1,024
    Thanks
    75
    Awards
    1

    Smile

    Quote Originally Posted by HeidiHectic View Post
    yes, i understand those im just not sure what to do after you distribute the exponent.
    \left(\frac{-6x^2y}{2xy^3}\right)^3

    =\frac{-216x^6y^3}{8x^3y^9}

    =\frac{-216}{8}\cdot\frac{x^6}{x^3}\cdot\frac{y^3}{y^9}

    =\frac{-27\cdot8}{8}\cdot\frac{x^6}{x^3}\cdot\frac{y^3}{y^  9}

    Now can you see how to continue?
    Follow Math Help Forum on Facebook and Google+

  5. #5
    -1
    e^(i*pi)'s Avatar
    Joined
    Feb 2009
    From
    West Midlands, England
    Posts
    3,053
    Thanks
    1
    Quote Originally Posted by HeidiHectic View Post
    I have to simplify this and im totally confused step by step help would be so much appreciated!
    <br />
\left( \frac {-6x^2y}{2xy^3} \right)^3<br />
    I'd cancel a factor of 2, x and y before cubing

    <br />
\left( \frac {-3x}{y^2} \right)^3 = \frac{-27x^3}{y^6}<br />
    Follow Math Help Forum on Facebook and Google+

  6. #6
    MHF Contributor Reckoner's Avatar
    Joined
    May 2008
    From
    Baltimore, MD (USA)
    Posts
    1,024
    Thanks
    75
    Awards
    1

    Smile

    Quote Originally Posted by e^(i*pi) View Post
    but 6^3 is 216?
    That's funny. Where did I get 36? It is a mystery.

    Quote Originally Posted by e^(i*pi) View Post
    I'd cancel a factor of 2, x and y before cubing
    This too. I went the other way because Heidi said she (or he) cubed first, but this is indeed easier.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Simplifying exponents
    Posted in the Algebra Forum
    Replies: 4
    Last Post: April 9th 2010, 04:46 PM
  2. simplifying exponents
    Posted in the Algebra Forum
    Replies: 2
    Last Post: September 21st 2008, 08:44 PM
  3. Simplifying exponents again....
    Posted in the Algebra Forum
    Replies: 1
    Last Post: October 28th 2007, 12:34 PM
  4. Simplifying with exponents
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: July 12th 2007, 03:39 AM
  5. Simplifying fractions with exponents
    Posted in the Algebra Forum
    Replies: 1
    Last Post: November 2nd 2006, 01:51 PM

Search Tags


/mathhelpforum @mathhelpforum