(log_(3) (log_(3) x)) = -1 solve for x
\(\Large log_3[log_3(x)]=-1\quad ?\)
yes
do you know how to convert log notation to exponential notation?
kind of this one would be 3^-1 = 1/3 so log_3(1/3) ?
because a^b=c and B^c=a
well, more or less, yes \(\bf log_3[log_3(x)]=-1\implies 3^{-1}=log_3(x)\implies \cfrac{1}{3}=log_3(x)\\ \quad \\ \cfrac{1}{3}=log_3(x)\implies \large 3^{\frac{1}{3}}=x\)
\(\large\bf 3^{\frac{1}{3}}=x\implies \sqrt[3]{3}=x\)
where do I go from here now? \[Log_3(1/3)=x?\]
I'm kind of lost on how we get to the end 3(1/3) part
what part?
After we get 1/3
\(\large \bf {\color{red}{\cfrac{1}{3}}=log_\color{blue}{3}(x)\implies \color{blue}{3}^{\color{red}{\frac{1}{3}}}=x\implies \sqrt[3]{3}=x}\)
all I did was convert it to exponent notation twice once for the outer function once for the inner one
so its 3^1/3?
yeap
and can be written at 3 root 3
yes
gotcha so one more question if you don't mind me asking
ok
Solve for X. 4 ^ (x- 4 ) = 3 Find an exact solution without decimals. You might want to use ln(x) or log(x).
\(\bf 4^{x- 4} = 3\\ \quad \\ \textit{using log cancellation rule of }\quad \color{blue}{log_aa^x=x}\qquad thus\\ \quad \\ 4^{x- 4} = 3\implies log_4(4^{x- 4} )=log_4(3)\implies x-4=log_4(3)\\ \quad \\ \textit{using the log change of base rule of }\quad \color{blue}{log_ab=\cfrac{log_cb}{log_ca}}\qquad thus\\ \quad \\ x-4=log_4(3)\implies x-4=\cfrac{log_{10}3}{log_{10}4}\implies x=\cfrac{log_{10}3}{log_{10}4}+4\)
how did we get the log_4(4^x-4)
we take \(\bf log_4\) to both sides
the idea being to use the log cancellation rule where the log base, MATCHES the base with the exponent
hence why they are both log base 10
why did I use the log change of base rule? well, technically I didn't have to but since calculators don't have \(\bf log_3 \ or \ log_4\ only \ log_{10} \ or \ ln\), thus
so I typed in the answer and said I got it wrong :((
now you know why the suggestion was "You might want to use ln(x) or log(x)"
I typed log3/log4+4
that's good, I used \(\bf log_{10}\) just to make it non-ambiguous, but yes, log with no base implies base 10
ohhh hmmm, well... I assume the answer expected is a value, so you have to get the logs first and add 4 to that
so just divide and add?
sorry for my lag :( yes, you have to divide and add
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