Решенный интеграл вида ∫xsin(x/α)dx

Solving an indefinite integral of the form ∫xsin(x/α)dx by integration by parts, where α takes the values 2,3,4,5...n
An example of solving integrals for α=3,6,7
∫xsin(x/α)dx, ∫xsin(x/3)dx, ∫xsin(x/6)dx, ∫xsin(x/7)dx

The solution is in PDF format