Advanced Math/Logarithms

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Expert: Sherry Wallin - 11/30/2010


Question
For the equation log y = log(0.5x-3) + log2,state the domain.Then express y as a function of x.
                           Thanks Very Much!  

Answer
Andrea~

The domain of the log function is that the log x, where x is greater than 0. In your problem
.5x-3 > 0 => .5x > 3 => x > 6, therefore log y = log(0.5x-3) + log2 has domain 6 < x < 00.

The sum of logs is the log of a product hence
log(0.5x-3)+log2 = log(2(.5x-3))= log (x - 6) thus
log y = log(x-6). This is base 10 so rewrite as an exponential equation:
10^(log (x-6)) = y => x - 6 = y which is the same as y = x - 6.

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Sherry Wallin

Expertise

I can answer most questions up through Calculus and some in Number Theory and Abstract Algebra.

Experience

I have had my Bachelor's Degree since 1987 and have been a teacher since 1988. I earned my Masters Degree in Mathematics May 2010. I have been teaching at the same community college since 2002.

Education/Credentials
I have taught 12 years at the community college level, medical college, and technical college as well as a high school instructor and alternative education instructor and charter school instructor.

Awards and Honors
Master's GPA 3.56 Bachelor's GPA 3.34 Post grad work not degree related GPA 4.0

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