# Mechanics of fluids

## Homework Statement

Small part of fluid which in the moment ##t=0## was at the point ##(X_1,X_2,X_3)## in some other moment is in the point ##(x_1,x_2,x_3)##. Where
$$x_1(t)=X_1$$
$$x_2(t)=X_2+\sin \pi t\sin \pi X_1$$
$$x_3(t)=X_3$$
We know that the piece of the fluid is in the t=0 in line which connects points ##(0,0,0)## i ##(1,0,0)##. Plot piece of the fluid at the moment ##t=\frac{1}{2},t=1## and ##t=\frac{3}{2}##.

## Homework Equations

As far as I undestand this is Lagrange formalism.

## The Attempt at a Solution

First of all I want to try to understand the problem. So that small part is one of the point in the line? Right? And every point in the line which connects points ##(0,0,0)## i ##(1,0,0)## changes with equations
$$x_1(t)=X_1$$
$$x_2(t)=X_2+\sin \pi t\sin \pi X_1$$
$$x_3(t)=X_3$$?
Right?