A LOG with a number in front of it

[susynmh02-disab]

Hello. I'm working on Logarithms right now. On the problems that I'm working on they have a number in front of LOG. What is it? And how do you go about solving it or entering it into StudyWorks? The problem that I'm on right now is:

5log(base 12)2

HELP!!

Thanks!

[TKHunny]

5log₁₂(2)

Do not become concerned, that 5 in front is just multiplication. It may be more clearly written:

5�log₁₂(2)

OR, with a logarithm property

log₁₂(2⁵)

Neither of these should pose much problem for entry into StudyWorks.

The Base 12, on the other hand, is a bit trickier, since StudyWorks does not have an arbitrary base placeholder on a logarithm function. All is not lost, however, knowing this principle:

log_b(a) = log_c(a) / log_c(b)

Where 'c' is anything valid (For example, -1 might be a bad choice and zero (0) would be a very bad choice.) c=10 is very popular before calculus. c=e is very popular after calculus.

Using c=10, then: (Recall log_{with no base written}() is assumed to be base 10)

log₁₂(2⁵) = log(2⁵) / log(12)

5�log₁₂(2) = 5�log(2) / log(12)

Thanks for joining us.

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[susynmh02-disab]

Thank you soooo much! I was beginning to wonder if that was the case, but I wasn't 100% sure since I have to teach this stuff to myself. This program is sooo useful!

Susy