# Math Help - laws of logarithms

1. ## laws of logarithms

this question is trickier than i'm used too...a little help please?

$log_{7}(49)(7) + log_{7}\sqrt{7}$

2. Hi there.

$log_7 49=2$

so $7log_7 49=7\times2$

and $log_7\sqrt{7}=\frac{1}{2}$

So $7log_7 49+log_7 \sqrt{7}=14\frac{1}{2}$

3. Originally Posted by Stroodle
Hi there.

$log_7 49=2$

so

i don't understand this part, why did the 7 move to the front of the log?

4. Because it's in a separate bracket to the 49, it means that the logarithm is multiplied by 7. I just put it in front because that's how it is conventionally written (at least in my texts).

5. Originally Posted by Stroodle
Hi there.

$log_7 49=2$

so $7log_7 49=7\times2$

and $log_7\sqrt{7}=\frac{1}{2}$

So $7log_7 49+log_7 \sqrt{7}=14+\frac{1}{2}" alt="7log_7 49+log_7 \sqrt{7}=14+\frac{1}{2}" />
you forgot a sign.

6. Originally Posted by Raoh
you forgot a sign.
I don't get it?

$14+\frac{1}{2}=\frac{29}{2}=14\frac{1}{2}$