Great Courses: The Secrets Of Mental Math, by Professor Arthur T. Benjamin
The professor of this great course is something he considers a mathemagician, the sort of person who is deeply passionate about mathematics  as well as in countering our dependence on technology in a way that can be immensely useful for students of standardized tests as well as those looking to impress people at cocktail parties. I enjoyed this series of lectures, for the most part, and would likely be interested in reading the author’s book if I was able to find it, which seems to cover the same material from what I have seen. This is a set of mathematical tricks and techniques that will test someone’s mental acuity and it is also one that has a great deal of practical use when it comes to being able to estimate and to turn difficult problems into simpler problems. Consider this course the anti-common core of mathematics, and that is a very good thing. Rather thank shrinking the number of tools, this is a six-hour course that provides a variety of tools in the knowledge that some of them will be easier to use than others in different circumstances and that it is worthwhile to become familiar with various circumstances to improve one’s skills at mental math.
The professor begins his course by talking about why people ought to be able to do math in their heads, which is a pretty rare concept within math education these days. After this the professor does a lecture on mental addition and subtraction, starting from the left rather than the right as is most common. After this comes two lectures, one dealing with multiplication and the other with division. The professor then looks at ways to combine mental math and paper to make hard problems easier to manage. A discussion of intermediate multiplication as well as the impressive speed of vedic and short division follows before the professor goes into the stranger material of memorizing numbers by using a letter code as well as using calendar calculating that comes off flat because it views Sunday as the seventh day of the week and praises pagan names rather than using biblical calendar calculation. The course then ends with lectures on advanced multiplication and practicing techniques in order to master mental math. The lectures demonstrate a professor who has a lot of passion about mathematics and a great deal of interest in sharing his tips and techniques with others.
Obviously for someone to get a lot out of this course someone should be interested in mathematics and have at least a decent enough memory to have the capacity to do calculation and estimation within one’s head. Besides this fairly obvious quality the ideal viewer of this professor should have a high tolerance for bad puns because he makes them often. Very often. How the viewer takes the combination of immense enthusiasm and a terrible sense of humor will depend on the individual but it is worthwhile at least to know what is coming. I enjoyed the slightly more than six hours of the course and thought it was worthwhile that the professor was willing to put himself to the test and show off his skills while also involving the audience to a large degree, which is always something that is enjoyable to see. Likewise, the practical benefit of what the professor has to say is something that makes this a course that should be well appreciated by those who take the time to enjoy this course on mental math.
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