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  1. #1
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    Help

    Solve the equation

    5^x = 1.4
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  2. #2
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     <br />
a^b = c \Rightarrow b = \log_a(c)<br />
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  3. #3
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    So what's

    Log5^1.4 =x
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  4. #4
    Senior Member Danneedshelp's Avatar
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    5^{x}=\frac{7}{5} \Rightarrow ln(5^{x})=ln(\frac{7}{5}) \Rightarrow {x}ln(5)=ln(\frac{7}{5})

    So, x=\frac{ln(\frac{7}{5})}{ln(5)}\approx{0.209062}

    ...

    Didn't mean to delete my work!
    Last edited by Danneedshelp; July 30th 2009 at 04:24 PM.
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  5. #5
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    Quote Originally Posted by garbles View Post
    So what's

    Log5^1.4 =x
    you mean x = \log_5(1.4)

    Do you have a calculator?
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  6. #6
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    Quote Originally Posted by Danneedshelp View Post
    ...

    What does this post mean?
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  7. #7
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    to work out \log_5{1.4}

    use

    \log_a{b}=\frac{\log_{10}{b}}{\log_{10}{a}}
    on the calc.
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