## №1, 2012

# APPROXIMATION TASK FOR GIVEN CLASSES OF MEMBERSHIP FUNCTIONS

Approximation task for triangular, trapezoidal, Gaussian, Bell and class of smooth membership functions was solved. Analytical formulas for gradients of target function for different classes of membership functions were recieved. Results of the minimization of target function and graphics of membership functions were demonstrated. (pp. 70-78)

**Keywords:**

*membership function, fuzzy sets, target function, approximation task*

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