Section 8.1 Reference

This site defines a logaithm and has practice worksheets.
http://www.math.utah.edu/~alfeld/math/log.html

This site gives an overview of logarithm:
http://hyperphysics.phy-astr.gsu.edu/hbase/logm.html

Review logarithms at this interactive site:
http://www.mathsdirect.co.uk/pure/purtutlogint.htm

Links