(1/3)^x-3 = 9
(1/3)^(x-3)=9 (1/3)^(x-3)=3^2 (1/3)^(x-3)=(1/3)^(-2) =>x-3=-2 =>x=1
\[\left(\frac{1}{3}\right)^x-3=9\] \[\left(\frac{1}{3}\right)^x=12\] \[x\phantom{.}\log_{10}\left(\frac{1}{3}\right)=\log_{10}12\] \[x=\frac{\log_{10}{12}}{\log_{10}(1/3)}\] \[x=\frac{\log_{10}12}{\log_{10}1-\log_{10}3}\] \[x=-\frac{\log_{10}12}{\log_{10}3}\approx2.26\]
Wait....im noticing that me and @sauravshakya 's answer is different...is the equation A or B: \[\eqalign{ &A.\phantom{spce}\left(\frac{1}{2}\right)^x-3=9 \\ &B.\phantom{spce}\left(\frac{1}{2}\right)^{x-3}=9 \\ }\]
B :D
Haha WOOOOW...k. wait.
and its 1/3
Err yeah haha
k. \[\eqalign{ &\left(\frac{1}{3}\right)^{x-3}=9 \\ &(3^{-1})^{x-3}=9 \\ &(x-3)\log_{3}3^{-1}=\log_{3}9 \\ &(x-3)(-1)=2 \\ &3-x=2 \\ &x=1 }\] To prove it: \[\eqalign{ &\left(\frac{1}{3}\right)^{x-3}=9 \\ &\left(\frac{1}{3}\right)^{1-3}=9 \\ &\left(\frac{1}{3}\right)^{-2}=9 \\ &\left[3^{(-1)}\right]^{-2}=9 \\ &3^{(-1\times-2)}=9 \\ &3^2=9 \\ &9=9 \\ }\] So, \(LS=RS \therefore QED\).
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