AU - Bazm, S AU - babolian, Esmaeil TI - Direct Numerical Solution of Fractional Differential, Integral and Integro-differential Equations by Using Numerical Inversion of Laplace Transform PT - JOURNAL ARTICLE TA - jsci JN - jsci VO - 11 VI - 2 IP - 2 4099 - http://jsci.khu.ac.ir/article-1-1428-en.html 4100 - http://jsci.khu.ac.ir/article-1-1428-en.pdf SO - jsci 2 ABĀ  - In this paper, we use operational matrices of piecewise constant orthog- onal functions on the interval [0,1] to solve fractional differential , integral and integro-differential equations without solving any system. We first ob- tain Laplace transform of the problem and then we find numerical inversion of Laplace transform by operational matrices. Numerical examples show that the approximate solutions have a good degree of accuracy. CP - IRAN IN - LG - eng PB - jsci PG - 161 PT - S YR - 2011