## anonymous 4 years ago Can someone break down the 5 rules of logarithms for me?

1. anonymous

$\log{a}+\log b=\log(ab)$ $\log a- logb=\log(a/b)$ $m \log a=\log a^m$ $\frac{\log a}{\log b}=\log_{b}a$ $x^{\log_xa}$

2. perl

you need a base c for your change of basis formula log_b a = log_c a / log_c b

3. lgbasallote

^actually...NotSObright is right...:)

4. perl

i didnt say its wrong, but it can be another base, than the default base

5. anonymous

i only remember power/ quotient/ and power rules was there more to it?

6. anonymous

product

7. perl

see above

8. anonymous

In all the above formulas is for all bases ob default valid until you use that same base

9. perl

all bases valid , yes

10. anonymous

so rules only apply or can be different under certain circumstances?

11. lgbasallote

depends on the situation

12. anonymous

You learn through practice

13. perl

ok here are some examples log 2 + log 3 = log (2*3). ln (2/3) = ln 2 - ln 3

14. perl

log 2 + ln 3 does not combine, because they are different bases

15. perl

log 2^3 = 3* log 2 , see if you can find which rule I used

16. perl

so log 8 = log (2^3) = 3 log 2 so log 8 = 3 log 2

17. anonymous

ok it cleared it up a bit ty m8

18. anonymous

rule of power right?

19. Directrix

Summary of log laws and demo problems at the link ---> http://www.themathpage.com/aprecalc/logarithms.htm#laws