A fallacy is an incorrect result arrived at by apparently correct, though actually specious reasoning. The most common example of
a mathematical fallacy is the ``proof'' that as follows. Let , then
References
Ball, W. W. R. and Coxeter, H. S. M. Mathematical Recreations and Essays, 13th ed.
New York: Dover, pp. 41-45 and 76-84, 1987.
Pappas, T. ``Geometric Fallacy & the Fibonacci Sequence.'' The Joy of Mathematics.
San Carlos, CA: Wide World Publ./Tetra, p. 191, 1989.