Mathematics
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OpenStudy (katherinesmith):
write 1-3log5x as a single logarithm
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OpenStudy (katherinesmith):
\[1 - 3\log _{5}x\]
OpenStudy (katherinesmith):
@jim_thompson5910
jimthompson5910 (jim_thompson5910):
how far did you get
OpenStudy (katherinesmith):
nowhere.
OpenStudy (katherinesmith):
i don't know what a single logarithm looks like
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jimthompson5910 (jim_thompson5910):
it looks like log(...) where the log is any base and there are no terms outside the log
OpenStudy (katherinesmith):
okay i know what you mean now
jimthompson5910 (jim_thompson5910):
try to get the given expression into the form I wrote
OpenStudy (katherinesmith):
i don't know how to go about doing that
OpenStudy (katherinesmith):
if someone could actually help me that would be great.
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jimthompson5910 (jim_thompson5910):
hints:
\[\large \log_{b}(b) = 1\]
\[\large y\log_{b}(x) = \log_{b}(x^y)\]
\[\large \log_{b}(x) - \log_{b}(y) = \log_{b}\left(\frac{x}{y}\right)\]
OpenStudy (katherinesmith):
okay i see your formulas but i have absolutely no idea what numbers are equivalent to what letters therefore i can't plug anything into a formula.
jimthompson5910 (jim_thompson5910):
you can replace b with 5 to go from
\[\large \log_{b}(b) = 1\]
to
\[\large \log_{5}(5) = 1\]
OpenStudy (katherinesmith):
okay i see that.
OpenStudy (katherinesmith):
then what.
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jimthompson5910 (jim_thompson5910):
use the other formulas I gave you
OpenStudy (katherinesmith):
what is y
jimthompson5910 (jim_thompson5910):
compare
\[\large y\log_{b}(x) \]
to
\[\large 3\log_{5}(x)\]
OpenStudy (katherinesmith):
\[3\log _{5}(x) = \log _{5}(x ^{3})\]
jimthompson5910 (jim_thompson5910):
good
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jimthompson5910 (jim_thompson5910):
we have this so far
\[\large 1 - 3\log_{5}(x)\]
\[\large \log_{5}(5) - 3\log_{5}(x)\]
\[\large \log_{5}(5) - \log_{5}(x^3)\]
OpenStudy (katherinesmith):
\[\log _{5}(x) - \log _{5}(3) = \log _{5}(\frac{ x }{ 3 })\]
jimthompson5910 (jim_thompson5910):
not quite
jimthompson5910 (jim_thompson5910):
\[\large \log_{5}(5) - \log_{5}(x^3)\]
turns into this
\[\large \log_{5}\left(\frac{5}{x^3}\right) \]
(see rule #3 given above)
jimthompson5910 (jim_thompson5910):
so this is the complete step by step picture
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jimthompson5910 (jim_thompson5910):
\[\large 1 - 3\log_{5}(x)\]
\[\large \log_{5}(5) - 3\log_{5}(x)\]
\[\large \log_{5}(5) - \log_{5}(x^3)\]
\[\large \log_{5}\left(\frac{5}{x^3}\right) \]
OpenStudy (katherinesmith):
and that's your answer huh
jimthompson5910 (jim_thompson5910):
yes
OpenStudy (katherinesmith):
thank you a ton for your patience
jimthompson5910 (jim_thompson5910):
sure thing