Решенный интеграл вида ∫xcos(x/α)dx

Solution of an indefinite integral of the form ∫xcos(x/α)dx by the method of integration by parts, where α takes the values 2,3,4,5...n
An example of solving integrals for α=2,4,5
∫xcos(x/α)dx, ∫xcos(x/2)dx, ∫xcos(x/4)dx, ∫xcos(x/5)dx

The solution is in PDF format