In the paper new representations for the functions cosⁿx and sinⁿx are obtained, which are effective for evaluation of many integrals, especially Kn=∫(x²+a²)⁻ⁿdx . It is found a primitive of the integral Kn in the explicit ...

In the paper it is shown that D’alembert’s test and Cauchy’s radical test are not independent one from another. It is proposed a transition scheme from one test to another and vice versa. The equivalence of the tests is ...