In the last section we made note of the fact that exponential functions pass the horizontal line test and thus have an inverse.
YouTube Playlist: Logarithms and their Graphs
Using the steps for finding the inverse we obtain:
Use the proper terminology when reading logarithms,
reads “log base 5 of 125 is 3.” If given
then x is called the argument of the logarithm. Also, notice that y is an exponent so the logarithm is actually an exponent, this will be important later.
Evaluate without using a calculator.
Instructional Video: Introduction to Logarithms
The base b can be any real number greater than zero but not including one - 10 and the natural base e are used often.
A logarithm without a base is interpreted as the common logarithm.
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