In q-analog theory, the Jackson integral series in the theory of special functions that expresses the operation inverse to q-differentiation.
The Jackson integral was introduced by Frank Hilton Jackson. For methods of numerical evaluation, see [1] and Exton (1983).
Let f(x) be a function of a real variable x. For a a real variable, the Jackson integral of f is defined by the following series expansion:
Consistent with this is the definition for
More generally, if g(x) is another function and Dqg denotes its q-derivative, we can formally write
giving a q-analogue of the Riemann–Stieltjes integral.
Just as the ordinary antiderivative of a continuous function can be represented by its Riemann integral, it is possible to show that the Jackson integral gives a unique q-antiderivative within a certain class of functions (see [2] ).
Suppose that If is bounded on the interval for some then the Jackson integral converges to a function on which is a q-antiderivative of Moreover, is continuous at with and is a unique antiderivative of in this class of functions. [3]
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