Wu Chong-shi
a0a1a2 a3 a4 a5 a6 a71
a8
a9a10a11 a12 a13 a14 a15
§3.1 a16 a17 a18 a19
a20a21a22a23a24a20a25a26a27a28a29a30a22a23a31a32C a24a20a26a27a28a29a33a30a34a35a25f(z)
a36C a28a37a38a39a31a40a33a30
C a41a42
a23a43a44n
a45
a34a23a46a44
z0 = A,z1,z2,···,zn = B,
ζk a24zk?1→zk a45
a28a29
a41a42a47
a46a34a48a49a25
nsummationdisplay
k=1
f(ζk)(zk ?zk?1) =
nsummationdisplay
k=1
f(ζk)?zk,
a50a51n→∞a34a52a53max|?z
k| → 0a54
a34a55a49a25a29a56a57a58
a36
a34a59
a60 ζ
k
a29a61a62a63a64a34a65a66a55a56a57a67a44a35a25 f(z)
a68
a33a30 C a29a22
a23a34a69a44
integraldisplay
C
f(z)dz = lim
max|?zk|→0
nsummationdisplay
k=1
f(ζk)?zk. a703.1
a47a71
a20a21a22a23a72a73a28a24a74
a71
a72a21a30a22a23a29a37a75a76a77
integraldisplay
C
f(z)dz =
integraldisplay
C
(u + iv)(dx + idy)
=
integraldisplay
C
(udx?vdy) + i
integraldisplay
C
(vdx + udy).
a78a55a34a79a80C a24a23
a45a81a82
a33a30a34 f(z)a24C a28a29a83a84a35a25a34a65a20a21a22a23
a47
a38a58
a36
a31
a20a21a22a23a29a85a86a87a88a89
1. a79a80a22a23
integraldisplay
C
f1(z)dz,
integraldisplay
C
f2(z)dz, ···,
integraldisplay
C
fn(z)dz a90
a58
a36
a34a65
integraldisplay
C
bracketleftBig
f1(z) + f2(z) +···+ fn(z)
bracketrightBig
dz =
integraldisplay
C
f1(z)dz +
integraldisplay
C
f2(z)dz +···+
integraldisplay
C
fn(z)dz;
2. a50C = C1 + C2 +···+ Cn a34a65integraldisplay
C1
f(z)dz +
integraldisplay
C2
f(z)dz +···+
integraldisplay
Cn
f(z)dz =
integraldisplay
C
f(z)dz;
3.
integraldisplay
C?
f(z)dz = ?
integraldisplay
C
f(z)dz a34a91a92C? a93a94C a29a95a96a97
4.
integraldisplay
C
af(z)dz = a
integraldisplay
C
f(z)dz a34a91a92aa44a98a25a97
5.
vextendsinglevextendsingle
vextendsingle
integraldisplay
C
f(z)dz
vextendsinglevextendsingle
vextendsingle ≤
integraldisplay
C
|f(z)||dz|a97
6.
vextendsinglevextendsingle
vextendsingle
integraldisplay
C
f(z)dz
vextendsinglevextendsingle
vextendsingle ≤ Mla34a91a92M a44
vextendsinglevextendsinglef(z)vextendsinglevextendsingle
a36C a28a29a28a99a34la44C a29a100a101a31
Wu Chong-shi
§3.1 a3 a4 a5 a6 a72a8
a102a103a34a20a21a22a23a29a25a67a104a105a106
? a107
a22a35a25a34
? a108
a46a109a110a34a111a22a23a29 a112a28a113a57a114a34
? a22a23a115a116a31
a117a106a118a38a29
a47a71a107
a22a35a25a34a51
a108
a46a119a38
a54
a34a117a106a120a121a29a22a23a115a116a34a22a23a67
a47a122
a24a120a121a29a31
a123 3.1
a124
integraldisplay
C
Rezdz a34 C a44 (i) a68
a72a125a1260 → 1 a34a127a26a128a106a129a125 1 → 1 + i a97 (ii)
a68
a129a125a126
0 → ia34a127a26a128a106a72a125 i → 1 + ia97(iii)a68a130
a300 → 1 + ia31
a131 a117a106(i)a34
integraldisplay
C
Rezdz =
integraldisplay 1
0
xdx +
integraldisplay 1
0
idy = 12 + i;
a117a106(ii)a34
integraldisplay
C
Rezdz =
integraldisplay 1
0
xdx = 12;
a117a106(iii)a34
integraldisplay
C
Rezdz =
integraldisplay 1
0
(1 + i)tdt = 12(1 + i).
Wu Chong-shi
a0a1a2 a3 a4 a5 a6 a73
a8
§3.2 a132a133a134a135a136a137 Cauchy a138a139
Cauchya38a140a141a142a29a24a22a23a67a60a22a23a115a116a143a144a29a64a145a31a60a146a147a29a148a149a37a64a31
a148a150a74a151a148a149a89
?a152a153a154a155a156
a89a157a158a159a160a161a162a163a164a165a166a167a168a169a34a168a169a170a171a172a173a174a175a176a158a159a97
?a177a153a154a155a156
a34a178a179a180a181a182a158a159a31
a703.2 a183a184a185a186a187a188a189a184a185a186a187
a152a153a154a155a156a190 Cauchy a191a192
a79a80a35a25f(z)
a36a193
a83a194a148a149 G a92a195a196a34a65
a68G a92a41a197a47a71
a23
a45a81a82
a29a198a77a199a200 C(
a201a2023.3)a37 contintegraldisplay
C
f(z)dz = 0,
a203a204a29C
a205a206a207
a24Ga29a208a99a31
a703.3 a183a184a185a186a187a209Cauchya210a211
Wu Chong-shi
§3.2 a212a213a214a215a216a217 Cauchya218a219
a74
a8
a220 a44a221
a193a222a201
a34a113a27
a36a223a224
a29a225a226a113a227a228a203
a71
a38a140a31a229a230a29a225a226a24 fprime(z)
a36G a92a83a84a231a31
a36
a55a225a226a113
a206a207a232a233 Greena234a235contintegraldisplay
C
bracketleftbigP(x,y)dx + Q(x,y)dybracketrightbig = integraldisplayintegraldisplay
S
parenleftbigg?Q
?x ?
?P
?y
parenrightbigg
dxdy
a106
contintegraldisplay
C
f(z)dz =
contintegraldisplay
C
bracketleftbigudx?vdybracketrightbig+ icontintegraldisplay
C
bracketleftbigvdx + udybracketrightbig,
a236a237a28a27a29a198a77a199a200a22a23a238a44a27a22a23
contintegraldisplay
C
parenleftbigudx?vdyparenrightbig = ?integraldisplayintegraldisplay
S
parenleftbigg?v
?x +
?u
?y
parenrightbigg
dxdy,
contintegraldisplay
C
parenleftbigvdx + udyparenrightbig = integraldisplayintegraldisplay
S
parenleftbigg?u
?x ?
?v
?y
parenrightbigg
dxdy.
a239a240Cauchy-Riemann
a241a242
a34a243
a108
a74
a71
a22a23a92a29
a107
a22a35a25a244a44 0a34a245a37
contintegraldisplay
C
f(z)dz = 0. square
a126a106Green
a234a235
a29a246
a124
a34a203a204a247a248a29
a193
a83a194a148a149a34a249a250a24
a47a71
a37a99a148a149a34a111a120a250a24a251a252 ∞a46
a36a253
a29(a63a99)a148a149a31 a254a255f(z)a157∞a172a0a1a34a2a3∞a172a4a5a171a6a7a8a9a10a11a12a13 0a31
Cauchy a38a140a14a47a71a15
a27a16a17a18a195a196a35a25a29
a47a71
a85a86a19a87a89 a0a1a20a21a157a2a171a0a1a158a159a170a34a22
a172a171a20a21a23a24a25a26a27a28a171a31
? Cauchy-Riemanna241a242
a24a203a151a64a29a29a30a23a31
a235
a34
? Cauchya38a140a65a24a32a29a22a23a31a235a31
a126Cauchya38a140a33a111
a206a207
a53a34a113a27a29a35a142a89
a36a37 a50f(z)
a36a193
a83a194a148a149G a92a195a196a34a65a20a21a22a23
integraldisplay
C
f(z)dz a60a115a116a63a64a31
(a131a38a39a40a190)a41a191a42a43 a44
a103
a36a193
a83a194a148a149a92a195a196a35a25a29a22a23a60a115a116a63a64a34a78a55a34a79a80a119a38
a222
a46z
0
a34a236a45a46a46z a44a21a46a34a65a48a44a22a23a28a57a29a35a25a34
integraldisplay z
z0
f(z)dz = F(z)
a24
a193
a83a194a148a149G
a253
a29
a193
a67a35a25a34a66a44 f(z)a29a120a38a22a23a31
a191a192 3.1 a79a80a35a25f(z)a36a193
a83a194a148a149G
a253
a195a196a34a65
F(z) =
integraldisplay z
z0
f(z)dz
a231 a47a48f(z)
a49Ga50a51a52a53
a54fprime(z)
a55a49a53
a56fprimeprime(z)
a57a55a49a53z ∈ Ga53
a58a59fprime(z)
a184a60a53
a54a61a62a63a64a65?u/?x,?u/?y,?v/?x
a66?v/?y
a184a60a67 a68
a7
a61a69
Wu Chong-shi
a0a1a2 a3 a4 a5 a6 a75
a8
a205a36G a253
a195a196a34a70a59
Fprime(z) = ddz
integraldisplay z
z0
f(z)dz = f(z).
a220 a249a246
a130a71a124a72 F(z)
a29a73a25a111
a206
a31
a703.5
a44a55a34a32z a24G
a253a47
a46a34z +?z a24a32a29a74a46a34a79
a202 3.5a34a65
F(z) =
integraldisplay z
z0
f(ζ)dζ, F(z +?z) =
integraldisplay z+?z
z0
f(ζ)dζ.
a78a44a22a23a60a115a116a63a64a34a247
a207
?F
?z =
F(z +?z)?F(z)
?z =
1
?z
integraldisplay z+?z
z
f(ζ)dζ.
a126a55
a206
a53
vextendsinglevextendsingle
vextendsinglevextendsingle?F
?z ?f(z)
vextendsinglevextendsingle
vextendsinglevextendsingle =
vextendsinglevextendsingle
vextendsinglevextendsingle
vextendsingle
1
?z
integraldisplay z+?z
z
f(ζ)dζ ?f(z)
vextendsinglevextendsingle
vextendsinglevextendsingle
vextendsingle
=
vextendsinglevextendsingle
vextendsinglevextendsingle
vextendsingle
1
?z
integraldisplay z+?z
z
bracketleftbigf(ζ)?f(z)bracketrightbigdζ
vextendsinglevextendsingle
vextendsinglevextendsingle
vextendsingle
≤ 1|?z|
integraldisplay z+?z
z
vextendsinglevextendsinglef(ζ)?f(z)vextendsinglevextendsingle·vextendsinglevextendsingledζvextendsinglevextendsingle.
a126a106f(z)a24a83a84a29a34a245a117a106
a41
a118a29 ε > 0a34a58
a36δ > 0a34a52a51|ζ?z| < δa54
a34|f(ζ)?f(z)| < εa34a247
a207vextendsingle
vextendsinglevextendsingle
vextendsingle
?F
?z ?f(z)
vextendsinglevextendsingle
vextendsinglevextendsingle ≤ 1
|?z| ·ε·|?z| = ε,
a111a53
Fprime(z) = lim
?z→0
?F
?z = f(z).
a203a75a227a228a18F(z)
a36G a253a206
a73a34a70a59Fprime(z) = f(z)a31 square
a76a39a40 a79a80a35a25Φ(z)a29a73a25Φprime(z) = f(z)a34a65Φ(z)a66a44f(z)a29a77a35a25a31a28a27a38a39a29f(z)
a29a120a38a22a23a75a24f(z)a29
a47a71
a77a35a25a31a117a106a118a38a29
a47a71
a35a25f(z)
a78
a248a34a77a35a25a120a24a79
a47
a29a31
a41a42
a74
a71
a77a35a25a143a144a249a80a81
a47a71
a98a25a31a203a24a78a44a34a79a80 Φ
1(z)
a60Φ
2(z)a90
a24f(z)a29a77a35a25a34a65
Φprime1(z) = f(z), Φprime2(z) = f(z).
Wu Chong-shi
§3.2 a212a213a214a215a216a217 Cauchya218a219
a76
a8
a247
a207
a34bracketleftbigΦ
1(z)?Φ2(z)
bracketrightbigprime = 0a34
Φ1(z)?Φ2(z) = C.
a82a200a18
a107
a22a35a25a29a77a35a25a34
a206
a52a20a21a22a23a29a83a84a85a44a221a238a31a32 Φ(z)a44f(z)a29
a47a71
a77a35a25a34a65
f(z)a29a120a38a22a23
F(z) =
integraldisplay z
z0
f(z)dz = Φ(z) + C.
a86a24a34a102a103a37
F(z0) = Φ(z0) + C = 0, C = ?Φ(z0).
a247
a207 integraldisplay
z
z0
f(z)dz = Φ(z)?Φ(z0).
a123 3.2 a83a84a22a23
integraldisplay b
a
zndz a34na44a87a25a31
a131 a51na44a88a103a25
a54
a34zn
a36a89
a26a27a195a196a34 1
n + 1z
n+1 a24a32a29
a47a71
a77a35a25a31a78a55a34a117a106 z a26a27
a28a29
a41a42a47
a225a22a23a115a30a34a244a37
integraldisplay b
a
zndz = 1n + 1bracketleftbigbn+1 ?an+1bracketrightbig.
a51n = ?2,?3,?4,···
a54
a34zn
a36
a120a251a252z = 0a46
a36a253
a29
a41a42a47a71a193
a83a194a148a149
a253
a195a196a34a91a77a35a25
a90
a206
a62a44 1
n + 1z
n+1 a31a78a55a34a90a37
integraldisplay b
a
zndz = 1n + 1bracketleftbigbn+1 ?an+1bracketrightbig.
a86a126a106a113
a47a91a92 3a29a77a78a34a55a93a80a117a106a120a251a252 z = 0a46a36a253
a29
a41a42
a148a149a244a94a33a31
a51n = ?1
a54
a34z?1
a205
a24
a36
a120a251a252z = 0
a36a253
a29
a41a47
a148a149
a253
a195a196a34a86a91a77a35a25
a232
a44 lnza31a78a55a34
a36
a120a251a252z = 0a29
a41a47a193
a83a194a148a149
a253
a34
integraldisplay b
a
dz
z = lnb?lna.
a95a246a19a150a96
a42
a34
a36a47a71a193
a83a194a148a149
a253
a34a28a27a29a22a23a51a103a60a115a116a63a64a31a86a24 a97a175a12a98a171a165a181a182
a158a159a34a98a99a171a100a172a101a102a172a8a103a104a105a106a12a98a171a6a7a23a31a14a83a84a29a107
a242a108
a34a203a204a29a77a35a25a24a109a67a35a25a34
a78a55a22a23a67a60a126aa21a238a34ba29
a241a235
a37a64a31a51a57a110
a36
a120a252z = 0a29
a47a71a193
a83a194a148a149
a253a54
a34a75a24a40 lnz
a57a110
a36a111a47a71a193
a67a23a112
a253
a34a245a22a23a67 lnb?lnaa24a79
a47a113
a38a29a31a236a117a106a120a121a29
a193
a83a194a148a149a34a75
a206
a250
a117
a232
a106lnz a29a120a121
a193
a67a23a112a34a78a236a22a23a67
a205
a75
a206
a250a120a121a31
Wu Chong-shi
a114a115a116 a117 a118 a119 a120 a1217
a122
§3.3 a16a133a134a135a136a137 Cauchy a138a139
a177a153a154a155a156a190 Cauchy a191a192
a79a80f(z)a24a20a83a194a148a149 G a92a29
a193
a67a195a196a35a25a34a65
contintegraldisplay
C0
f(z)dz =
nsummationdisplay
i=1
contintegraldisplay
Ci
f(z)dz,
a91a92C
0,C1,C2,···,Cn
a24a123a94a20a83a194a148a149Ga29a208a99a29a124
a71
a23
a45a81a82
a198a77a33a30a34C
1,C2,···,Cn a90
a251
a252
a36C0 a29a253a125
a34a236a59a247a37a29a22a23a115a116a126a96a80a121a31
a703.6 a189a184a185a186a187a209Cauchya210a211
a220 a79
a2023.6a34a120a127a62C0, C1, C2, ···, Cn a244a44a95a54a128a241
a96a31a48a129a51a29a43a30a40C
1, C2, ···, Cn
a49
C0 a83a93a222a78
a34a14a236a53a34
a47a71a193
a83a194a148a149Gprime a34f(z)
a36a193
a83a194a148a149Gprime
a253
a24a195a196a29a34a78a236
a206a207a232a233a193
a83a194a148a149a29 Cauchya38a140a34
contintegraldisplay
C0
f(z)dz +
integraldisplay b1
a1
f(z)dz +
contintegraldisplay
C?1
f(z)dz +
integraldisplay a1
b1
f(z)dz
+
integraldisplay b2
a2
f(z)dz +
contintegraldisplay
C?2
f(z)dz +
integraldisplay a2
b2
f(z)dz +···
+
integraldisplay bn
an
f(z)dz +
contintegraldisplay
C?n
f(z)dz +
integraldisplay an
bn
f(z)dz = 0.
a126a106f(z)
a36Gprime a253a193
a67a34a245
a68
a121
a47
a43a30a74a130a29a22a23a67a131a80a132a133a34
integraldisplay bi
ai
f(z)dz +
integraldisplay ai
bi
f(z)dz = 0.
a247
a207 contintegraldisplay
C0
f(z)dz +
nsummationdisplay
i=1
contintegraldisplay
C?i
f(z)dz = 0, (3.1)
contintegraldisplay
C0
f(z)dz = ?
nsummationdisplay
i=1
contintegraldisplay
C?i
f(z)dz =
nsummationdisplay
i=1
contintegraldisplay
Ci
f(z)dz. square (3.2)
Wu Chong-shi
§3.3 a3a213a214a215a216a217 Cauchya218a219
a78
a8
a123 3.3 a83a84
contintegraldisplay
C
zndz a67a34na44a87a25a34C a29a126a96a44a95a54a128a241a96a31
a131 a51na44a88a103a25
a54
a34a102a103a34a134a135
a193
a83a194a148a149a29 Cauchya38a140
contintegraldisplay
C
zndz = 0.
a51na44a136a87a25
a54
a34a79a80 C
a253
a120a252z = 0a34a65
a205
a37
contintegraldisplay
C
zndz = 0.
a79a80C
a253
a252a37z = 0a34a65a134a20a83a194a148a149a29 Cauchya38a140a34a37
contintegraldisplay
C
zndz =
contintegraldisplay
|z|=1
zndz
=
integraldisplay 2pi
0
parenleftbigeiθparenrightbign eiθidθ = integraldisplay 2pi
0
ei(n+1)θidθ
=
?
?
?
2pii, n = ?1;
0, n = ?2,?3,?4,···.
a137a93a28a27a29a93a80a34a75a37
contintegraldisplay
C
zndz =
??
?
2pii, n = ?1, a59Ca253a252a37z = 0;
0, a91a138a139a31.
a140a141a34
a223a47a122a142
a34
contintegraldisplay
C
(z ?a)ndz =
?
?
?
2pii, n = ?1, a59Ca253
a252a37z = a;
0, a91a138a139a31.
Wu Chong-shi
a0a1a2 a3 a4 a5 a6 a79
a8
§3.4 a143a144a145a146a137a147a139
a148
a192 3.1
a79a80a35a25f(z)
a36z = aa46a29a74a149a253a83a84a34
a70a59a51 θ
1≤ arg(z ?a)≤ θ2, |z ?a| → 0a54
a34(z ?a)f(z)
a47a149a142
a150a151a106 k a34a65
lim
δ→0
integraldisplay
Cδ
f(z)dz = ik(θ2 ?θ1),
a91a92C
δ
a24
a207 z = a a44a152a153a34 δ a44a154a116a34a155a156a44 θ2 ? θ1 a29a152
a157a34|z ?a| = δ, θ
1 ≤ arg(z ?a) ≤ θ2
a34
a201a2023.7a31
a220 a78a44
integraldisplay
Cδ
dz
z ?a = i(θ2 ?θ1),
a703.7
a247
a207 vextendsingle
vextendsinglevextendsingle
vextendsingle
integraldisplay
Cδ
f(z)dz ?ik(θ2 ?θ1)
vextendsinglevextendsingle
vextendsinglevextendsingle =
vextendsinglevextendsingle
vextendsinglevextendsingle
integraldisplay
Cδ
bracketleftbigg
f(z)? kz ?a
bracketrightbigg
dz
vextendsinglevextendsingle
vextendsinglevextendsingle
≤
integraldisplay
Cδ
|(z ?a)f(z)?k| |dz||z ?a|.
a126a106a51θ
1 ≤ arg(z ?a) ≤ θ2
a34z ?a → 0
a54
a34(z ?a)f(z)
a47a149a142
a150a151a106ka34a203
a42a158a159?ε > 0a34?(a60
arg(z ?a)a63a64a29) r(ε) > 0a34a52a51|(z ?a)| = δ < ra54
a34|(z ?a)f(z)?k| < εa31a247
a207vextendsingle
vextendsinglevextendsingle
vextendsingle
integraldisplay
Cδ
f(z)dz ?ik(θ2 ?θ1)
vextendsinglevextendsingle
vextendsinglevextendsingle ≤ ε(θ2 ?θ1),
a111
lim
δ→0
integraldisplay
Cδ
f(z)dz = ik(θ2 ?θ1). square
Wu Chong-shi
§3.4 a160a161a162a163a217a164a219
a710
a8
a148
a192 3.2
a32 f(z)
a36 ∞ a46a29a74a149a253a83a84a34a51 θ1 ≤
argz ≤ θ2 a34z → ∞a54
a34zf(z)
a47a149a142
a150a151a106K a34a65
lim
R→∞
integraldisplay
CR
f(z)dz = iK(θ2 ?θ1),
a91a92C
R
a24
a207
a77a46a44a152a153a34Ra44a154a116a165a155a156a44θ
2?θ1
a29a152a157a34
|z| = R, θ1 ≤ argz ≤ θ2 (a201a2023.8)a31
a220 a55a166a140a29a227a228a49 a148
a192 3.1
a29a227a228a80a167a31a78a44
integraldisplay
CR
dz
z = i
parenleftbigθ
2 ?θ1
parenrightbiga34a247
a207 a703.8
vextendsinglevextendsingle
vextendsinglevextendsingle
integraldisplay
CR
f(z)dz ?iK(θ2 ?θ1)
vextendsinglevextendsingle
vextendsinglevextendsingle =
vextendsinglevextendsingle
vextendsinglevextendsingle
integraldisplay
CR
bracketleftbigg
f(z)? Kz
bracketrightbigg
dz
vextendsinglevextendsingle
vextendsinglevextendsingle
=
vextendsinglevextendsingle
vextendsinglevextendsingle
integraldisplay
CR
bracketleftbigzf(z)?Kbracketrightbigdz
z
vextendsinglevextendsingle
vextendsinglevextendsingle ≤
integraldisplay
CR
vextendsinglevextendsinglezf(z)?Kvextendsinglevextendsingle· |dz|
|z| .
a126a106a51θ
1 ≤ argz ≤ θ2
a34z → ∞
a54
a34zf(z)
a47a149a142
a150a151a106K a34a203
a42a158a159?ε > 0
a34?(a60argz a63a64
a29)M(ε) > 0a34a52a51|z| = R > M
a54
a34|zf(z)?K| < εa31a247
a207vextendsingle
vextendsinglevextendsingle
vextendsingle
integraldisplay
CR
f(z)dz ?iKparenleftbigθ2 ?θ1parenrightbig
vextendsinglevextendsingle
vextendsinglevextendsingle ≤ ε(θ2 ?θ1),
a111
lim
R→∞
integraldisplay
CR
f(z)dz = iKparenleftbigθ2 ?θ1parenrightbig. square