## $$\mathcal A$$-summability and approximation of continuous periodic functions.(English)Zbl 1199.41137

The paper is concerned with sequences of positive linear operators defined on the space of real-valued continuous $$2\pi$$-periodic functions. The author gives a generalization of the classical Korovkin theorem (with 1, $$\cos x$$ and $$\sin x$$ as test functions) by using a matrix summability method.

### MSC:

 41A36 Approximation by positive operators 47B38 Linear operators on function spaces (general)

### Keywords:

matrix summability; Korovkin type theorem