Hi;

how do you multiply logs ie log[base2](4) * log[base2](16) I think you work out each log seperately then multiply the solution,Is this the correct process?

Here I get 8.

Also do I do the same thing with different bases?

Thanks.

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- Aug 28th 2011, 10:33 AManthonyemultiplying logs
Hi;

how do you multiply logs ie log[base2](4) * log[base2](16) I think you work out each log seperately then multiply the solution,Is this the correct process?

Here I get 8.

Also do I do the same thing with different bases?

Thanks. - Aug 28th 2011, 10:47 AMSironRe: multiplying logs
Your answer is correct.

Just use the definition like you've done.

$\displaystyle \log_a(x)=y \Leftrightarrow a^y=x$ - Aug 28th 2011, 10:50 AManthonyeRe: multiplying logs
Ok do I do the same thing with different bases?

- Aug 28th 2011, 10:54 AMSironRe: multiplying logs
It depends, for example if you've different bases you can use:

$\displaystyle \log_a(x)\cdot \log_x(y)=\log_a(y)$

For example:

$\displaystyle \log_2(4)\cdot \log_4(16)=\log_2(16)=4$

And offcourse you can use the definition.

$\displaystyle \log_2(4)\cdot \log_4(16)=2\cdot 2=4$

Is this clear?... - Aug 28th 2011, 11:15 AManthonyeRe: multiplying logs
got to take a break from study back tommorow.

Thanks. - Aug 28th 2011, 11:31 AMSironRe: multiplying logs
You're welcome! :)

- Aug 28th 2011, 01:19 PManthonyeRe: multiplying logs
No thats not clear.

- Aug 28th 2011, 01:47 PMSironRe: multiplying logs
What's not clear? ...

- Aug 28th 2011, 01:52 PManthonyeRe: multiplying logs
Until I know more will the way I did it work for the same and different bases?

- Aug 28th 2011, 01:56 PMSironRe: multiplying logs
What you did is fine, but using this log rules can be really useful sometimes. What have you learned yet about logarithms? Only the definition? ...

- Aug 28th 2011, 01:59 PManthonyeRe: multiplying logs
Yeah not much just doing logs now.