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ω 1 F<br />

<br />

<br />

1 F <br />

<br />

ω 1 F (x) = F1(x, y, z) dx + F2(x, y, z) dz + F3(x, y, z) dz.<br />

ω<br />

+γ<br />

1 F (x) =<br />

<br />

<br />

=<br />

+γ<br />

+γ<br />

F1(x, y, z) dx + F2(x, y, z) dz + F3(x, y, z) dz<br />

y dx − y dy<br />

γ x = cos θ y = sin θ <br />

<br />

ω 1 <br />

F (x) =<br />

2π<br />

y (dx − dy) = sin θ · (− sin θ + cos θ) dθ<br />

+γ<br />

= −<br />

+γ<br />

2π<br />

0<br />

sin 2 θ = −<br />

0<br />

2π<br />

0<br />

1 − cos 2θ<br />

2<br />

dθ = −π.<br />

<br />

<br />

∂F3 ∂F2<br />

rot F := −<br />

∂y ∂z ,<br />

∂F1 ∂F3<br />

−<br />

∂z ∂x ,<br />

<br />

∂F2 ∂F1<br />

− ,<br />

∂x ∂y<br />

<br />

= −100x 5 z 99 , −2yz<br />

(1 + z2 ) 2 − 2x, 5x4z 100 − 1<br />

1 + z2 <br />

<br />

<br />

<br />

<br />

<br />

0 = div(rotF ) dxdydz = rot F dσ = rot F · ˆn dσ + rot F · ˆn dσ,<br />

C<br />

Σ<br />

<br />

<br />

rot F · ˆn dσ = − rot F · ˆn dσ,<br />

S<br />

D<br />

D C ˆn = (0, 0, −1) rotF = (0, −2x, −1)<br />

<br />

<br />

<br />

<br />

rot F · ˆn dσ = − rot F · ˆn dσ = (−1) dxdy<br />

S<br />

D<br />

D<br />

D −π <br />

<br />

<br />

ω 1 <br />

F (x) = −π = rot F · ˆn dσ,<br />

+γ<br />

<br />

S z = xy/2 x 2 +y 2 ≤ 12<br />

S F = (x, y, 1) S <br />

<br />

S z = f(x, y) f : D → R f(x, y) = xy/2 <br />

D := {(x, y) ∈ R 2 : x 2 + y 2 ≤ 12} D √ 12 = 2 √ 3<br />

dσ S <br />

<br />

dσ = 1 + |∇f| 2 <br />

= 1 + y2 x2 1<br />

+ dx dy = 4 + y2 + x2 dx dy.<br />

4 4 2<br />

S<br />

S<br />

D

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