This article aims to introduce two effective numerical approaches for solving the mixed linear fractional Volterra-Fredholm integro-differential equation (FVIDE) and multi-higher order with initial conditions. Even though these approaches transfer the integro-differential equations into a system of algebraic equations through operational matrices of generalized block pulse functions, these problems can be transferred to a system of algebraic equations by expanding the solution's multi-highest order derivative through the block pulse functions (BPFs). The block pulse operational matrices for fractional-order integration are derived by expanding the Riemann-Liouville fractional integral for repeated fractional integration in block pulse functions (BPFs). Also, the fractional derivative is done by using the generalized operational matrices of BPFs with the fractional calculus properties in the first scheme. The methods are attractive in the calculation, and examples are supplied to explain their use. The estimated and exact outcomes are compared in a table. In addition, they decrease the error terms in the specified domain using the least squares-error technique. For this, most general programs are written in Python V.3.8.8 software (2021).
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