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> N.A. Kudryashov. Seven common errors in finding exact solutions of nonlinear differential equations
Abstract
We analyze the common errors of the recent papers in which the solitary wave solutions of nonlinear differential equations are presented. Seven common errors are formulated and classified. These errors are illustrated by using multiple examples of the common errors from the recent publications. We show that many popular methods in finding of the exact solutions are equivalent each other. We demonstrate that some authors look for the solitary wave solutions of nonlinear ordinary differential equations and do not take into account the well  known general solutions of these equations. We illustrate several cases when authors present some functions for describing solutions but do not use arbitrary constants. As this fact takes place the redundant amount of the solutions of differential equations are found. A few examples of incorrect solutions by some authors are presented. Several other errors in finding the exact solutions of nonlinear differential equations are discussed.
Contents
 Introduction
 First error: some authors use equivalent methods to find exact solutions
 Second error: some authors do not use the known general solutions of ordinary differential equations
 Third error: some authors omit arbitrary constants after integration of equation
 Fourth error: using some functions in finding exact solutions some authors lose arbitrary constants
 Fifth error: some authors do not simplify the solutions of differential equations
 Sixth error: some authors do not check solutions of differential equations
 Seventh error: some authors include additional arbitrary constants into solutions
 Conclusion
 References
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