Abstract:
We consider the problem of inversion of the Laplace transform by means of a special series with respect to Laguerre polynomials, which in a particular case coincides with the Fourier series in polynomials $l_{r,k}^{\gamma}(x)$$(r\in \mathbb{N}, k=0,1,\ldots)$, orthogonal with respect to a scalar product of Sobolev type of the following type
\begin{equation*}
<f,g>=\sum\nolimits_{\nu=0}^{r-1}f^{(\nu)}(0)g^{(\nu)}(0)+\int_0^\infty f^{(r)}(t)g^{(r)}(t)t^\gamma e^{-t}dt, \gamma>-1.
\end{equation*}
Estimates of the approximation of functions by partial sums of a special series with respect to Laguerre polynomials are given.
Keywords:Laplace transforms, Laguerre polynomials, special series.