1. Show that this expression is a total differential of the function u (x, y). Find u (x, y) function
1.19. (20x3 - 21x2y + 2y) dx + (3 + 2x - 7x3) dy

2. Solve the following tasks:
2.19. Calculate the moments of inertia about quarter circle arc axes x = 2cost, y = 2sint, lying in the first quadrant.

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