Fuzzy differential equation
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. for all  . First order fuzzy differential equation 
A first order fuzzy differential equation with real constant or variable coefficients 

 

where  is a real continuous function and  is a fuzzy continuous function
 such that . Application 
It is useful for calculating Newton's law of cooling, compartmental models in epidemiology and multi-compartment model. Linear systems of fuzzy differential equations 
A system of equations of the form 

where  are real functions and  are fuzzy functions

Fuzzy partial differential equations 
A fuzzy differential equation with partial differential operator is 
for all . Fuzzy fractional differential equation
A fuzzy differential equation with fractional differential operator is 

  for all  where  is a rational number. References 

 Fuzzy logic
 Differential equations