# Fuzzy Solution of Interval Nonlinear Equations

• Ludmila Dymova
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6068)

## Abstract

In [10,12], a new concept of interval and fuzzy linear equations solving based on the generalized procedure of interval extension called “interval extended zero” method has been proposed. The central for this approach is the treatment of “interval zero” as an interval centered around 0. It is shown that such proposition is not of heuristic nature, but is a direct consequence of interval subtraction operation. It is shown that the resulting solution of interval linear equation based on the proposed method may be naturally treated as a fuzzy number. In the current report, the method is extended to the case of nonlinear interval equations. It is shown that opposite to the known methods, a new approach makes it possible to get both the positive and negative solutions of quadratic interval equation.

## Keywords

interval nonlinear equation fuzzy solution interval zero

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