In his work Researches on the precession of the equinoxes and nutation of the earth, he provided a mathematical description of those phenomena, while another work of his analyzed the problem of a vibrating string, which led him to develop his namesake solutions to the 1-D wave equation, which involve rightward and leftward travelling waves.  His namesake principle applies Newton's second law to vi
In his work Researches on the precession of the equinoxes and nutation of the earth, he provided a mathematical description of those phenomena, while another work of his analyzed the problem of a vibrating string, which led him to develop his namesake solutions to the 1-D wave equation, which involve rightward and leftward travelling waves.  His namesake principle applies Newton's second law to virtual displacements, and calculates the virtual work done on a system.  His namesake operator is the second-time derivative minus the Laplacian, and is symbolized by a box, and he showed that a body in an inviscid, incompressible fluid should experience no drag, which is his namesake paradox.  FTP, identify this Frenchman who edited most of the science in the Encyclopédie.
In his work Researches on the precession of the equinoxes and nutation of the earth, he provided a mathematical description of those phenomena, while another work of his analyzed the problem of a vibrating string, which led him to develop his namesake solutions to the 1-D wave equation, which involve rightward and leftward travelling waves.  