The author of the identity involving e to the i theta is, for 10 points, what Swiss mathematician who is the namesake of the base of the natural logarithm?
This mathematician's name is given to a line that passes through the orthocenter, circumcenter, and centroid of a triangle. His phi function yields the amount of numbers between 1 and n that are relatively prime to n. He solved the Seven Bridges of Konigsberg problem, and his polyhedral formula states that vertices plus faces minus edges equals 2. The author of the identity involving e to the i theta is, for 10 points, what Swiss mathematician who is the namesake of the base of the natural logarithm?
This mathematician's name is given to a line that passes through the orthocenter, circumcenter, and centroid of a triangle.
Leonhard {Euler}