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Homework Help: (non)fractional Negative Exponents

  1. Mar 8, 2006 #1
    We got thirty questions dealing with zero and negative exponents, but I'm having trouble with the negative exponent questions.

    An example of this is:

    a^3b-2/3^-1a^4b^-3

    (-3x^-2y^3/3^-3x^4y^8)^-2

    Sorry if these two examples look messy I don't know how to write it out like people write equations on this site.
     
  2. jcsd
  3. Mar 8, 2006 #2

    Hurkyl

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    You could still use parentheses correctly. And spaces are terrific for readability. E.G. I think you meant to write:

    a^3 b^-2 / (3^-1 a^4 b^-3)

    for the first one.
     
  4. Mar 8, 2006 #3
    Thanks for the tip Hurkyl. Do you have any ideas on how to solve them?
     
  5. Mar 8, 2006 #4
    You should know (and remember) these relations when dealing with exponents:

    [tex]x^{a}x^{b}=x^{a+b}[/tex] and [tex]\frac{x^{a}}{x^{b}}=x^{a-b}[/tex].

    And, of course, [tex]x^{a}y^{b}\neq xy^{a+b}[/tex] and the same for the fractions.

    Hint: If you click on the LaTeX images above you can see the code and learn how to use it in this forum.
     
  6. Mar 8, 2006 #5
    Thanks for the tip Assyrian.

    But if you have a solution to the above problems it would definitely give me a kick start to my homework.
     
  7. Mar 8, 2006 #6
    Sorry, but solutions are not just given away. You have to show your work. What have you done so far on these problems?
     
  8. Mar 8, 2006 #7
    Well I think I've actually figured out the first one, I'm working on the second one rigt now but i might have it in a minute. here's my work for the first one by the wya, tell me if I got it right:
    [tex]\frac{a^{3}b^{-2}} {3^{-1}a^{4}b^{-3}}[/tex]

    [tex]=3a^{-1}b[/tex]

    [tex]=\frac{3b} {a}[/tex]

    if you cant see th LaTeX, I probobly put it in wrong, here's my work in plain text:

    (a^3 b^-2) / (3^-1 a^4 b^-3)

    = 3a^-1 b

    =(3b) / a
     
  9. Mar 8, 2006 #8
    That looks correct. And yes, I can see the LaTeX.
     
  10. Mar 8, 2006 #9
    Thanks assyrian :)

    Well I've looked at a few math help sites and a few tutorials, got some help from a teacher today, and didn't understand the lesson in calss yesterday, but I finally understand it :p

    talk about dedication to the "arts" :)
     
  11. Mar 8, 2006 #10
    Can you explain something to me though?

    I have a question that's written like this [tex]x^{2}y^{-3}[/tex] but I have no clue as to what they're asking of me.
     
  12. Mar 8, 2006 #11
    I don't know what the question is either. :smile: Do they want you to simplify [tex]x^{2}y^{-3}[/tex] or what?
     
  13. Mar 8, 2006 #12
    I have no clue and they don't tell you what you're supposed to do on the worksheet, which really sucks.

    Well I thank you for your assistance Assyrian, but I'm going to go watch Harry Potter and the Goblet of Fire now while I redue all of my homework.

    Thanks again, bye.
     
  14. Mar 8, 2006 #13
    Interesting....I'm soon to go and watch the same movie. :smile:
     
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