Sal Khan
Log-a-what? No, this tutorial is about neither chopped wood nor music (actually logarithms do have applications in music), but it is fascinating nonetheless. You know how to take an exponent. Now you can think about what exponent you have to raise a numbe. Source: Khan Academy (www.khanacademy.org), used under the Creative Commons Attribution-NonCommercial-ShareAlike (CC BY-NC-SA) license. All Khan Academy content is available for free at www.khanacademy.org. Khan Academy does not endorse the World Public Library.
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