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Negative exponents and scientific notation

  1. Apr 14, 2005 #1
    holy cow i feel dumb....

    i know these are super easy but i just can't figure it out.

    1. --- (10^2)^8 divided by (10^-2)^3

    2. --- 1.2x10^-6 divided by 4.2x10^-2

    if anyone can give me a kick in the brain it would be awsome

    1.--- 10^22?
    2. -- 2.9x10^5??
    Last edited: Apr 14, 2005
  2. jcsd
  3. Apr 14, 2005 #2
    The first one is correct. The second is not (but only by a sign, typo ?). To check, multiply your quotient by the divisor to see if you get the dividend.
  4. Apr 14, 2005 #3


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    [tex]1.2\cdot10^{-6}\div\left(4.2\cdot10^{-2}\right)= 1.2\cdot10^{-6}\cdot\frac{1}{4.2}\cdot10^2= \frac{1.2}{4.2}\cdot10^{-4}=\frac27\cdot10^{-4}\approx2.9\cdot10^{-5}[/tex]
  5. Apr 14, 2005 #4
    no it wasn't a typo...just dumb
    thank you so much, it is amazing how fast you forget stupid things
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