Inter should beat Cagliari, even though they have a very difficult return match in the Champions League with Bayern, they also need to think about not letting Napoli get any closer to them. Especially since they have drawn with Milan and Parma twice in a row and they were lucky that Napoli also lost points, but this will not continue forever, so Inter should beat Cagliari at home. Napoli will most likely beat Empoli at home, and Inzaghi would not want them to be tied on points.
The match was a little easier because Inter Milan dominated every match and it didn't take long for Inter Milan to get their first goal through Arnautovic, after that it was Martinez and Bisseck's turn so that Inter managed to secure three points in the match and this victory makes them even more likely to achieve the Scudetto this season in the remaining matches.
Napoli will face Empoli in the next two days so they must secure full points in order to close the gap in points from Inter Milan and if they fail then it is almost certain that Napoli will have difficulty competing for the title with Inter Milan in the remaining matches.