Hello,

Please respond with answers to these questions, they have already been
completed, I just need vertification of my answer, and more
importantly a more detailed explanation.  I do not want to post my
answers here, Im not a big fan of google indexing this and possibly
making this available to my students.  I am not just looking for
answers, but more importantly ways to explain this to my students.  A
couple sentence answers will do.

1.  What is the value of log -1?  Explain.
2.  What is the domain of the function g(x) = log x
3.  X = -6 and Y = -7.  Why is log (XY) [NOT EQUAL TO] log X + log Y?
Please Expand on your answer on this one.

Thank you very much.

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Request for Question Clarification by mathtalk-ga on 19 Dec 2002 11:14 PST

Hi, teachadvice-ga:

The best ways to explain these answers to your students might depend
on their level of study.  Would it be possible to identify whether
these are grade school, high school, college, or graduate students?

thanks in advance,
mathtalk-ga

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Clarification of Question by teachadvice-ga on 19 Dec 2002 11:19 PST

These are high-school students.  At this point I am looking for
extremely brief answers.  Thanks

Hi,

here it goes.

1. the function log (-1) does not exist in real numbers, it is only
defined for the values of x>0.

2. domain log x = ( 0 ; + inf) note that 0 (zero) is not contained as
domain in x > 0

3. log x.y = log x + log y is a valid property only when x > 0 and y >
0

in this cases
-6 < 0 and -7 < 0.

you cannot calculate log (x y) or log (-6)(-7) first you must multiply
the negative signs (-)(-) = (+) = log 42

therefore

=log 6 + log 7

regards