On Fréchet and Gateaux Derivatives for Interval and Fuzzy-Valued Functions in the Setting of Gh-Differentiability

We present new results in the calculus for interval functions of multiple real variables in the setting of gH-differentiability and, based on a new concept of interval linear functions, we define and analyse Gateaux and Frechet́ differentiability and their properties. Finally, the results obtained for interval-valued functions are easily extended (level-wise) to define linear fuzzy-valued functions and corresponding Gateaux-Fréchet fuzzy differentiability.