“…The estimates were derived for the Caputo and RiemannLiouville fractional derivatives with fractional derivatives 0 < δ 1 < 1 and 1 < δ 2 < 2. These results were used to develop new maximum principles and establish existence and uniqueness results for several types of fractional equations [1, 3, 5-7, 11, 17], and to develop numerical schemes for certain fractional differential equations [16,18,22]. Also, the results concerning the Riemann-Liouville fractional derivative, were used and generalized for weaker conditions on [6,18].…”