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S<br />

<br />

rotF · ˆn dσ =<br />

+∂S<br />

<br />

F dγ = 2 2 2 2<br />

+ − =<br />

3 3 3 3 ,<br />

S <br />

ϕ(θ, y) = ( y 2 + 1 cos θ, y, y 2 + 1 sin θ), θ ∈ [0; 2π], |y| < 1<br />

F (x, y, z) = (x 2 , y/2, x) S <br />

(1, 0, 0) e1 = (1, 0, 0)<br />

ϕ(θ, y) = (ϕ1, ϕ2, ϕ3) F = (F1, F2, F3) <br />

Jac ϕ(θ, y) =<br />

⎛<br />

⎜<br />

⎝<br />

− y 2 + 1 sin θ<br />

y cos θ<br />

√ y 2 +1<br />

<br />

0 1<br />

y2 + 1 cos θ<br />

√y sin θ<br />

y2 +1<br />

ˆn = (n1, n2, n3)<br />

(1, 0, 0)<br />

⎛<br />

n1 −<br />

⎜<br />

det ⎜<br />

⎝<br />

y2 + 1 sin θ<br />

n2 <br />

0 1<br />

y2 + 1 cos θ<br />

n3<br />

y cos θ<br />

√ y 2 +1<br />

√y sin θ<br />

y2 +1<br />

⎞<br />

⎟<br />

⎠<br />

(θ,y)=(0,0)<br />

⎛<br />

= det ⎝<br />

⎞<br />

⎟<br />

⎠ .<br />

1 0 0<br />

0 0 1<br />

0 1 0<br />

<br />

⎞<br />

⎠ = −1 < 0.<br />

Φ(S, ⎛<br />

2π F1 ◦ ϕ −<br />

1 ⎜<br />

F ) = − det ⎜<br />

⎝<br />

0 −1<br />

y2 y cos θ<br />

+ 1 sin θ √<br />

y2 +1<br />

F2 ◦ ϕ 0 1<br />

F3 ◦ ϕ y2 ⎞<br />

⎟<br />

⎠ dy dθ<br />

y sin θ<br />

+ 1 cos θ √<br />

y2 +1<br />

⎛<br />

2π (y<br />

1 ⎜<br />

= − det ⎜<br />

⎝<br />

0 −1<br />

2 + 1) cos2 θ − y2 ⎞<br />

y cos θ<br />

+ 1 sin θ √<br />

y2 +1 ⎟<br />

<br />

y/2 0 1 ⎟<br />

⎠ dy dθ<br />

y2 + 1 cos θ y2 y sin θ<br />

+ 1 cos θ √<br />

y2 +1<br />

⎛<br />

2π 1<br />

= − (−y/2)det ⎝<br />

0 −1<br />

−y2 ⎞<br />

y cos θ<br />

+ 1 sin θ √<br />

y2 +1 ⎠ dy dθ+<br />

y2 + 1 cos θ<br />

2π<br />

−<br />

= −<br />

1<br />

0 −1<br />

2π 1<br />

0<br />

= − 2<br />

3 π.<br />

−1<br />

y sin θ<br />

√ y 2 +1<br />

<br />

(y2 + 1) cos2 θ − y2 + 1 sin θ<br />

(−1)det dy dθ<br />

y2 + 1 cos θ y2 + 1 cos θ<br />

y 2 1 2π <br />

/2 dy dθ + (y<br />

−1 0<br />

2 + 1) 3/2 cos 3 θ + (y 2 <br />

+ 1) sin θ cos θ dθ dy

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