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    I think I'm missing something simple here guys. If you help me with the first question i should be able to work out the rest.

    Given that, in standard form, 3^{236}=4\times10^{112} and 3^{-376}=4\times10^{-180} find approximations, also in standard form, for the following.

    a) 3^{376}
    b) 3^{612}
    c) (\sqrt3)^{236}
    d) (3^{-376})^\frac{5}{2}

    As I said before, a little help with what to do for the first one would be appreciated. For a) I think im going to have to do something to 3^{-376}=4\times10^{-180} to get the answer, but im not sure what.
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    Take the reciprocal. So 1/4 x 10^180 which is equal to 2.5 x 10^179.
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    Thanks, that was annoyingly simple .
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     3^{-376} = (3^{376})^{-1} so surely  3^{376} = \frac{1}{4 \times 10^{-180}}
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    Ok I have worked out a), b), and c) but i cant do d). Any help?
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    (Original post by PhyMath)
    Ok I have worked out a), b), and c) but i cant do d). Any help?
     (ab)^2 = a^2 b^2

    so

     (ab)^{\frac{5}{2}} = a^{\frac{5}{2}} b^{\frac{5}{2}}

    Does that help?
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    Well, the ^(5/2) means square root it and then to the power of 5. Rt (3^-376) = 2 x 10^-90 (from the definition), and then to the power of 5, so 32 x 10^-450 or 3.2 x 10^-449.
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    (Original post by quakeeem)
    Well, the ^(5/2) means squa...
    I was trying to get him to work it out himself :no:
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    There aren't two terms in the bracket, 3^{-376} is one term.

    Nvm, i get it now. Thanks guys.
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    :yy:
 
 
 
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