1. { ξ 1 , ξ 2 , ξ 3 } {\displaystyle \{\xi ^{1},\xi ^{2},\xi ^{3}\}} — Lagrangian coordinates, { x , y , z } {\displaystyle \{x,y,z\}} — Eulerian coordinates.
Law of medium motion is given:
x = ξ 1 + ( ξ 1 + ξ 2 ) ln ( 1 + t ) {\displaystyle x=\xi ^{1}+(\xi ^{1}+\xi ^{2})\ln(1+t)} y = ξ 2 + ( ξ 1 − ξ 2 ) ln ( 1 + t ) {\displaystyle y=\xi ^{2}+(\xi ^{1}-\xi ^{2})\ln(1+t)} z = ξ 3 + ( ξ 1 + ξ 2 ) ln ( 1 + t ) {\displaystyle z=\xi ^{3}+(\xi ^{1}+\xi ^{2})\ln(1+t)}
Find components of velocity and acceleration as functions of Lagrangian and Eulerian variables.
— Lagrangian coordinates, 
— Eulerian coordinates.
