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Homework Help: Powers Expressions

  1. May 12, 2005 #1
    Evalulate, leaving the answer as a fraction:


    a) [tex]\left(\frac{4}{9}\right)^\frac{3}{2}[/tex]


    b) [tex](-27)^-^\frac{1}{3}[/tex]

    Please Help.
    Thanks
     
  2. jcsd
  3. May 12, 2005 #2

    Imo

    User Avatar

    Some useful hints:

    [tex] a^\frac{b}{c} = (a^b)^\frac{1}{c} = (a^\frac{1}{c})^b [/tex]

    [tex] a^-^b = \frac{1}{a}^b [/tex]

    [tex] a^\frac{1}{b} = \sqrt{a} [/tex]

    hope that helps
     
  4. May 12, 2005 #3
    And to add on to Imo's hints, remember that an exponent is written in the form of [tex]\frac{\mbox{power}}{\mbox{root}}[/tex]

    For instance, [tex]9^{\frac{3}{2}} = (\sqrt{9})^3[/tex]
     
  5. May 12, 2005 #4
    Thank you, I finally got it. I lost my math notes and my exam is coming pretty soon so I needed to review.
     
  6. May 12, 2005 #5
    [tex]a^-^b = \frac{1}{a^b} = \left(\frac{1}{a}\right)^b [/tex]
     
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