Question

log(5)70=____?
round the final answer 4 decimal places.

Answer 1

> log(5)*70
[1] 112.6607

Answer 2

\[\text{Let } k = \log_5(70)\]\[\implies 5^k = 70\]\[\implies \log(5^k) = \log(70)\]\[\implies k\log(5) = \log(70)\]\[\implies k = \frac{\log(70)}{\log(5)}\]\[\implies \log_5(70) = \frac{\log(70)}{\log(5)}\]

Answer 3

thanks, but that's incorrect apparently mapologo

Answer 4

so....

Answer 5

i just divide 70 by the base (5), and get 14... but what to do about the 'log' part??

Answer 6

No. You divide the log of 70 by the log of the base.

Answer 7

ugh...

Answer 8

2.6397??

Answer 9

It's the change of base 'formula' but I can't bother remembering it so I derive it each time.

Answer 10

Yeah, that's right.

Answer 11

sweet!!! thanks!

Answer 12

please review the steps and make sure you understand what was done, and why.

Answer 13

I shall try!!

Answer 14

it seems simple enough, it's just remembering all the different steps for different types of problems that's difficult. :)