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Expert: Sherry Wallin - 3/30/2010


Question
-1 < log_3^y < 1
=> -3 < y < 3

please explain it

Answer
Pratap~
    Basically the statement says that if the log base 3 of y is between -1 and 1 exclusive then y must be between -3 and 3 exclusive. (exclusive means you can't include the end points). How do you know/show/prove this? Raise each term in the first expression and find it's exponential:
3^(-1) < y < 3^1
which of course is 1/3 < y < 3. Note 3^-1 is 1/3^1 = 1/3. Did you make a mistake with your second inequality typing it in? Regardless, the 2nd statement is still true since if y is between 1/3 and 3, it is certainly between -3 and 3 too.

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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.

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

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