Anger has its place, but it will not serve you here, the way of the warrior is the way of knowing. Of that knowledge requires you to use anger, then you use anger, but you cannot wrest forth knowledge by losing your temper.
All great fighting is the same, Eragon, even as all great warriors are the same. Past a certain point, it does not matter whether you wield a sword, a claw, a tooth or a tail. It is true, you must be capable with your weapon, but anyone with the time, and the inclination can acquire technical proficiency. To achieve greatness, though, that requires artistry. That requires imagination and thoughtfulness, and it is those qualities that the best warriors share, even if, on the surface, they appear completely different.