The AMATYC Review
Fall 2005, Vol.27, No.1
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Classroom Issues with Series
Tests
Jawad Sadek and Russell Euler
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Jawad Sadek is an associate professor of mathematics at Northwest
Missouri State University in Maryville. His main interests include
complex analysis, problem solving, his students' questions, and
soccer. E-mail: jawads@mail.nwmissouri.edu
Russell Euler is a professor in the Department of Mathematics and
Statistics at Northwest Missouri State University. His interests
include analysis, geometry, and number theory. Presently he is the
Problems Editor for the Elementary Problems and Solutions section
of The Fibonacci Quarterly. E-mail: reuler@mail.nwmissouri.edu
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| We find infinite series in calculus to
be one of the most confusing topics our students encounter. In this
note, we look at some issues that our students find difficult or ambiguous
involving the Ratio Test, the Root Test, and also the Alternating
Series Test. We offer some suggestions and some examples, which could
be a supplement to the set of the exercises in the standard calculus
texts, to help alleviate these difficulties. Precisely, we discuss
the issue of the relationship between the Ratio Test and the Root
Test as well as some misconceptions that students may have when applying
the Alternating Series Test. In particular, students often fail to
understand the importance of checking that the sequence is nonincreasing.
We also point out how they may even confuse the concept of alternating
terms. |
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