# Euler's equations

As **Euler equations** or **Euler equations** are called:

- Euler's equations (fluid mechanics) for the flow of frictionless fluids
- Euler's equations (gyroscopic theory) for the rotation of rigid bodies

Further equations named after Leonhard Euler:

- Euler's differential equation
- Euler-Lagrange equation, see calculus of variations
- Euler's equation for the geometry of the triangle, see Euler's line # properties
- Euler-Fuß's equation on the question of when in the Euclidean plane there is a convex quadrangle for two given circles lying one inside the other, which is both the chordal quadrilateral of the larger circle and the tangent quadrilateral of the smaller circle (geometry)
- Euler equation for internal energy (thermodynamics), see Internal Energy # Several types of material (K> 1)
- Euler equation of consumption (economics)

after postponement

**See also:**

- Euler's formula , polar representation of complex numbers
- Euler's angle , description of the orientation of a body in space