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arXiv · 1807.04125

Evaluation of some non-elementary integrals involving sine, cosine, exponential and logarithmic integrals: Part II

Victor Nijimbere
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Abstract

The non-elementary integrals $\mbox{Si}_{\beta,\alpha}=\int [\sin{(\lambda x^\beta)}/(\lambda x^\alpha)] dx,\beta\ge1,\alpha>\beta+1$ and $\mbox{Ci}_{\beta,\alpha}=\int [\cos{(\lambda x^\beta)}/(\lambda x^\alpha)] dx, \beta\ge1, \alpha>2\beta+1$, where $\{\beta,\alpha\}\in\mathbb{R}$, are evaluated in terms of the hypergeometric function $_{2}F_3$. On the other hand, the exponential integral $\mbox{Ei}_{\beta,\alpha}=\int (e^{\lambda x^\beta}/x^\alpha) dx, \beta\ge1, \alpha>\beta+1$ is expressed in terms of $_{2}F_2$. The method used to evaluate these integrals consists of expanding the integrand as a Taylor series and integrating the series term by term.

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Victor Nijimbere. 2018-06-29. Evaluation of some non-elementary integrals involving sine, cosine, exponential and logarithmic integrals: Part II. https://doi.org/10.15826/umj.2018.1.004

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