I.4.27 Curvilinear Integrals

Condition: Find the curvilinear integral of the vector \ (\ vec {a} = \ left (y z-x^{2} \ right) \ vec {\ iMath}+\ left (x z-y^{2} \ right) \ vec {\ jmath}+\ left (x y-z^{2} \ right) \ vec {k} \ quad \) in the circumference \ (x = r \ cos t, y = r \ sin t \), \ (z = 0 \) lying in the 1st octress, from the point from the point \ (M (r, 0.0) \) to the point \ (n (0, r, 0) \).