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AllThatYouDreamed
June 4th, 2011, 08:15 AM
Home stretch of school, I'm on Logs.

Does anyone know any sites I could go on that could help explain this shit, because my teacher is utterly POINTLESS and barely knows what SHE'S doing, let alone how to teach this.

Thanks :)
Magus
June 4th, 2011, 09:34 AM
Logs - as in doing arithmetic with logs?
Jess
June 4th, 2011, 09:49 AM
go here: http://www.purplemath.com/modules/logs.htm

this gives a nice explanation
AllThatYouDreamed
June 5th, 2011, 03:15 PM
That does help a bit, it sets the groundwork so I SHOULD be able to figure out the next part before the test. Yeah, my teacher teaches fuckall and this is honors precalc. Not to mention I missed the first day of explanation.

We're also doing log translations, which supposedly follow graphical translations, but don't seem to IMO, and converting into common/natural logs so it can be typed into the calculator

Logs - as in doing arithmetic with logs?
..Yeah, we're totally doing our math homework on wooden logs now.
Magus
June 5th, 2011, 04:10 PM
Yeah, we're totally doing our math homework on wooden logs now.I don't appreciate shitty sarcasm.
You think I don't know what logarithm is?

I once asked about logarithm (http://www.virtualteen.org/forums/showthread.php?t=67909) before. But that one involved arithmetic. That's why I asked that question.

But fuck, some people are... what to say?
AllThatYouDreamed
June 5th, 2011, 05:40 PM
OK, well what you've said is still confusing me.
By "arithmetic with logs" do you mean like how (using common log for sake of typing)
log(A)-log(B)=log(A/B)
or something else entirely?
Magus
June 6th, 2011, 11:51 AM
or something else entirely?

+ = * / for big numbers, we use log tables (http://www.oldcomputers.arcula.co.uk/bhist3.htm). Before, it was in the syllabus, but now cancelled, but we are still using it in Science.
AllThatYouDreamed
June 6th, 2011, 04:17 PM
+ = * / for big numbers, we use log tables (http://www.oldcomputers.arcula.co.uk/bhist3.htm). Before, it was in the syllabus, but now cancelled, but we are still using it in Science.

Somehow, I think I'll be seeing this in college. Thanks :)
Marky
June 14th, 2011, 09:42 PM
log(a) + log (b) = Log (ab)

log(a) - log (b) = Log (a/b)

(a) times log (b) = log (b^a)


logrithms are exponents X^m=b logx(b) = m

we did all this in algebra2. i think the last one is wrong. but hey i hope i helped. going into pre cal in august :D I love math anyother questions i can help u with?