Logarithm... write with same base
\[\log _{2}12+\log _{4}6-\log _{2}24\]
So obviously I start with the middle log... that has the base of 4 to change it to base 2... \[4^{x}=6\] \[(2^{2})^{x}=6\] \[2^{2x}=6\]
Which means... \[\log _{2}6=2x\]
How do I simplify this even more?
I know the answer is... \[\frac{ 1 }{ 2 }\log _{2}6 = \log _{2}6^{\frac{ 1 }{ 2 }}\]
I just don't know how you jump to that...
@MathLegend Try to combine what you can for now Then simplify it
use the division property first log(a)-log(b)=log(a/b) for the ones that have the same base
ok
\[\log _{2}(\frac{ 12 }{ 24 })+\log _{4}6\]
great so far but 12/24 reduces
Oh, I wasn't sure if we were allowed to reduce.. because my teacher never does with logs. \[\log _{2}(\frac{ 1 }{ 2 })+\log _{4}6\]
ok so that 1/2 is very important here because you know log_2(1)=? and you know log_2(2)=?
\[\log_2(\frac{1}{2})=\log_2(1)-\log_2(2)=? \]
-1 ?
so you have \[-1+\log_4(6) \]
now if you want to write this as one log with one base you can
\[1=\log_a(a)\]
where a>0 and not equal to 1 of course :)
Okay, so should I do what I did earlier to have this change to... \[2^{2x}=6 = \log _{2}6=2x\]
\[\log _{2}6=2x\]
You don't need that do you mean 2^(2x)=6 implies log_2(6)=2x
replace the 1 in your problem with log_4(4) so the bases will match
\[-1+\log_4(6)=-\log_4(4)+\log_4(6)=\log_4(6)-\log_4(4)\] you should be able to take it from here
\[\log _{4}(\frac{ 3 }{ 2 })\]
that's great
But the answer says... \[\log _{2}(\frac{ \sqrt{6} }{ 2 })\]
it looks like they also wrote it with base 2 instead of base 4 so if you want it in base 2 you will need to play with our answer some more
\[\log_4(\frac{3}{2})=\frac{\log_2(\frac{3}{2})}{\log_2(4)} \text{ (By change of base formula ) }\] \[=\frac{\log_2 (\frac{3}{2})}{\log_2(2^2)}\] do you got from here?
I'm confused on how you just went from base 4 to base 2 in the numerator and the denominator... because isn't the formula... \[\log _{b}M=\frac{ logM }{ logb }\]
\[\frac{ \log4 }{ \log \frac{ 3 }{ 2 } }\]
Am I utilizing the formula incorrectly?
Ok sorry was eating... but yeah the formula is \[\log_b(M)=\frac{\log_a(M)}{\log_a(b)}\] We want a to be 2 so I replaced a's with 2 M was 3/2 to I replaced M with 3/2 everywhere else b was 4 so I replaced all the b's with 4
|dw:1398543261227:dw| when comparing these two you should see that..
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