Simplify log₁₀(3/√(1+x)) using logarithm rules

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0range
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Homework Statement



Write the quantity using sums and differences of simpler logarithmic expressions. Express the answer so that logarithms of products, quotients, and powers do not appear.

[tex]log_{10}\frac{3}{\sqrt{1+x}}[/tex]


Homework Equations





The Attempt at a Solution



Handwritten derivation on graph paper: log10 of 3 over the square root of (1+x), then log10 3 minus log10 of (1+x) to the power 1/2, then log10 3 minus 1/2 log10 (1+x).


The book's answer, however, is [tex]3log_{10}x-\frac{1}{2}log_{10}(1+x)[/tex]

Thanks in advance!
 
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0range said:

Homework Statement



Write the quantity using sums and differences of simpler logarithmic expressions. Express the answer so that logarithms of products, quotients, and powers do not appear.

[tex]log_{10}\frac{3}{\sqrt{1+x}}[/tex]


Homework Equations





The Attempt at a Solution



Handwritten log work on graph paper, rotated sideways: log10(3/(1+x)^(1/2)) = log10 3 - log10((1+x)^(1/2)) = log10 3 - (1/2) log10(1+x).


The book's answer, however, is [tex]3log_{10}x-\frac{1}{2}log_{10}(1+x)[/tex]

Thanks in advance!

Check the original question to make sue the numerator is just 3 and not an exponential
 
Hi, thanks for the reply.

No, the original equation is as appears.
 
Must be a typo in the book, then. Possibly whoever typed up the answer key thought that the problem was
[tex]log_{10}\frac{x^3}{\sqrt{1+x}}[/tex]
 
Oh, so I'm right? How anti-climatic...

Thanks again.