1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Easy exponential question-> 1/3(8)^(-2/3)

  1. Nov 13, 2012 #1
    Easy exponential question---> 1/3(8)^(-2/3)

    1. The problem statement, all variables and given/known data

    I am doing a linear approximation question, and got stuck here with this simple stuff.


    Can anyone explain what I need to do to turn the above into 1/12 ?

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Nov 13, 2012 #2
    Re: Easy exponential question---> 1/3(8)^(-2/3)

    $$8^{\frac{-2}{3}} = \frac{1}{8^{\frac{2}{3}}}$$
  4. Nov 13, 2012 #3

    Ray Vickson

    User Avatar
    Science Advisor
    Homework Helper

    Re: Easy exponential question---> 1/3(8)^(-2/3)

    What you have written reads as
    [tex] \frac{1}{3} 8^{-2/3}.[/tex] Is that what you meant, or did you want
    [tex] \frac{1}{3\, 8^{-2/3}}?[/tex]
    If you mean the first one you should use brackets, like this: (1/3) 8^(-2/3), but if you mean the second one you should write 1/(8 2^(-2/3)).

  5. Nov 14, 2012 #4


    User Avatar
    Science Advisor

    Re: Easy exponential question---> 1/3(8)^(-2/3)

    As BloodyFrozen said, 8-2/3= 1/82/3. Further, since 23= 8, 81/3= 2 and so 82/3= 22= 4.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook