Justify that, for all $( p , q ) \in \left( \mathrm { N } ^ { * } \right) ^ { 2 }$, the series $\sum u _ { k }$ converges, where $u_k = \dfrac{(-1)^k}{pk+q}$.
Justify that, for all $( p , q ) \in \left( \mathrm { N } ^ { * } \right) ^ { 2 }$, the series $\sum u _ { k }$ converges, where $u_k = \dfrac{(-1)^k}{pk+q}$.