Fuzzy differential equation

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Fuzzy differential equation are general concept of ordinary differential equation in mathematics defined as differential inclusion for non-uniform upper hemicontinuity convex set with compactness in fuzzy set.{{r|routledge|11th-national|dongqiu}}

dx(t)/dt= F(t,x(t),\alpha), for all \alpha \in [0,1] .

First order fuzzy differential equation

A first order fuzzy differential equation{{r|keshavarz}} with real constant or variable coefficients

x'(t) + p(t) x(t) = f(t)

where p(t) is a real continuous function and f(t) \colon [t_0 , \infty) \rightarrow R_F is a fuzzy continuous function

y(t_0) = y_0 such that y_0 \in R_F .

Linear systems of fuzzy differential equations

A system of equations of the form

x(t)'_n = a_n1(t) x_1(t) + ......+ a_nn(t) x_n(t) + f_n(t) where a_ij are real functions and f_i are fuzzy functions

x'_n(t)= \sum_{i=0}^1 a_{ij} x_i.

Fuzzy partial differential equations

A fuzzy differential equation with partial differential operator is

\nabla x(t) = F(t,x(t),\alpha),for all \alpha \in [0,1] .

Fuzzy fractional differential equation

A fuzzy differential equation with fractional differential operator is

\frac {d^n x(t)} {dt^n}= F(t,x(t),\alpha), for all \alpha \in [0,1] where n is a rational number.

References

{{reflist|refs=

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Category: Fuzzy logic

Category: Differential equations