Solve for "x" 2(3^x)=12^x-1.
Is this it? \[2\times3^x=12^{x-1}\]?
yes
this one takes a minute gimmick is to write \[12=3\times 4\] so \[12^{x-1}=3^{x-1}4^{x-1}\] then divide both sides of \[2\times 3^x=3^{x-1}4^{x-1}\] by \(3^{x-1}\)
maybe @Ahsome has a slicker way, not sure if that method is best
maybe adding a log will help?
Hmmm..
Would we use logarithim?
i believe so
once you ave \[6=4^{x-1}\] you would use the change of base formula so yes, logarithms for sure
but that is the last step, not the first step
how did you get there?
According to wolframalpha, \[x\approx2.2925\]
i wrote the steps above take a look and see if you have any questions about how i got to \[6=4^{x-1}\]
\[2×3^x=12^{x−1}\] \[3^x=\frac{12^{x−1}}{2}\] \[log_3{\frac{12^{x−1}}{2}}=x\]
Hmmm
which you and also write as \[24=4^x\] making \[x=\frac{\ln(24)}{\ln(4)}\]
yeah i get that
Wait a minute is: \[2×3^x=12^{x−1}\] The same as: \[2×3^x=12^{x}\div12^1?\]
How did you go from 12=3×4 to 12^x-1=3^x-14^x-1
Me, or @satellite73?
\[2×3^x=12^{x−1}\] \[2×3^x=12^x÷12^1\] \[12(2\times3^x)=12^x\] \[log_{12}{12(2\times3^x)}=x\]
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