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ω = ωx dx + ωy dy<br />

∂yωx = ∂xωy x 2 + y 2 = 0<br />

∂<br />

∂y<br />

x + By<br />

x 2 + y 2<br />

<br />

B(x 2 + y 2 ) − (x + By)2y<br />

(x 2 + y 2 ) 2<br />

= ∂<br />

∂x<br />

Cx + y<br />

x 2 + y 2<br />

<br />

= C(x2 + y 2 ) − (Cx + y)2x<br />

(x 2 + y 2 ) 2<br />

Bx 2 + By 2 − 2xy − 2By 2 = Cx 2 + Cy 2 − 2Cx 2 − 2xy<br />

(B − C)(x 2 + y 2 ) = 2By 2 − 2Cx 2<br />

(x, y) ∈ R 2 \ {0, 0} x = 0 y = 1 <br />

B −C = 2B C = −B 2B(x 2 +y 2 ) = 2By 2 +2Bx 2<br />

B ∈ R ω C = −B<br />

C = −B ω Ω <br />

Ω (1, 1) <br />

<br />

u(x, y) = ω,<br />

γ (x,y)<br />

γ (x,y) Ω (x, y) ∈ Ω (1, 1) ∈ Ω <br />

u(1, 1) = 0 γ (x,y) <br />

C = −B<br />

u(x, y) =<br />

=<br />

x<br />

1<br />

x<br />

= 1<br />

2<br />

1<br />

x<br />

1<br />

ωx(t, 1) dt +<br />

y<br />

y<br />

1<br />

ωy(x, s) ds<br />

t + B<br />

t2 + 1 +<br />

Cx + s<br />

1 x2 ds<br />

+ s2 2t + 2B<br />

t2 + 1 +<br />

y<br />

1<br />

Cx + s<br />

x2 ds<br />

+ s2 = 1<br />

2 [log(t2 + 1) + 2B arctan t] t=x<br />

t=1 +<br />

y<br />

1<br />

Cx + s<br />

x2 ds<br />

+ s2 = 1<br />

2 log(x2 + 1) + B arctan x − log √ 2 − Bπ<br />

4 +<br />

= 1<br />

2 log(x2 + 1) − C arctan x − log √ 2 + Cπ<br />

4 +<br />

= 1<br />

2 log(x2 + 1) − C arctan x − log √ 2 + Cπ<br />

4 +<br />

+ C<br />

y<br />

1<br />

1<br />

<br />

s<br />

1 +<br />

x<br />

2<br />

ds<br />

x<br />

+ 1<br />

2 [log(x2 + s 2 )] s=y<br />

s=1<br />

= 1<br />

2 log(x2 + 1) − C arctan x − log √ 2 + Cπ<br />

4 +<br />

+ C<br />

y/x<br />

1/x<br />

y<br />

1 1<br />

dz +<br />

1 + z2 2 log(x2 + y 2 ) − 1<br />

2 log(x2 + 1)<br />

= −C arctan x − log √ 2 + Cπ<br />

4<br />

<br />

u(1, 1) = −C arctan 1 − log √ 2 + Cπ<br />

4<br />

Cx + s<br />

x2 ds<br />

+ s2 1<br />

y Cx<br />

1 x2 y s<br />

ds +<br />

+ s2 1 x2 ds<br />

+ s2 + C arctan(y/x) − C arctan 1/x + 1<br />

2 log(x2 + y 2 ).<br />

1<br />

+ C arctan(1) − C arctan(1) + log(2) = 0.<br />

2

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