# Tagged Questions

**10**

votes

**1**answer

331 views

### Who first resolved Hilbert's 20th problem?

Hilbert's 20th problem concerns the existence of solutions to the fundamental problem in the calculus of variations. I understand that Hilbert, Lesbesgue and Tonelli were pioneers in this area.
In ...

**6**

votes

**3**answers

617 views

### Who came up with the Euler-Lagrange equation?

Which man came up with the solution to the basic Calculus of Variations problem first?
http://en.wikipedia.org/wiki/Euler-Lagrange
Makes it sound like Lagrange got it first in 1755, then sent it to ...

**12**

votes

**3**answers

2k views

### What was Weierstrass's counterexample to the Dirichlet Principle?

Shortly after his work on the foundations of geometry David Hilbert turned his attention to finding a suitable statement of the Dirichlet principle, from which to prove the Riemann mapping theorem and ...