1. Show that this expression is a total differential of the function u (x, y). Find u (x, y) function
1.5. (1 / (x + y) + cosxcosy-3x2) dx + (1 / (x + y) -sinxsiny + 4y) dy

2. Solve the following tasks:
2.5. Calculate the moment of inertia about the axis Oy semicubical arc of a parabola y2 = x3, between the points with abscissas x = 0 and x = 4/3.

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