Терехина Фикс ВМ 2
.PDFsLEDSTWIQ IZ WTOROGO "ZAME^ATELXNOGO PREDELA" |
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lim |
ln(1 + (x)) |
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lim |
loga(1 + (x)) |
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(x) |
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ln a |
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(x)!0 |
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lim |
e (x) ; 1 |
= 1 |
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a (x) ; 1 |
= ln a |
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(x)!0 |
(x) |
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(x)!0 |
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1.2.5. sRAWNENIE BESKONE^NO MALYH WELI^IN |
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pUSTX DANY DWE BESKONE^NO MALYE PRI x ! x0 (ILI x ! 1) WELI- |
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^INY (x) I (x): dLQ NIH SPRAWEDLIWO |
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lim (x) = 0 |
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tEM NE MENEE, HARAKTER (SKOROSTX) IH PRIBLIVENIQ K NUL@, WOOB]E GO- WORQ, MOVET BYTX RAZNYM. pO\TOMU GOWORQT O PORQDKE MALOSTI ODNOJ B.M.W. OTNOSITELXNO DRUGOJ.
~TOBY SRAWNITX DWE BESKONE^NO MALYE WELI^INY NUVNO NAJ- TI PREDEL IH OTNO[ENIQ.
rASSMOTRIM WOZMOVNYE SLU^AI.
1. pREDEL OTNO[ENIQ (x) K (x) RAWEN NUL@
lim (x) = 0
x!x0 (x)
TOGDA BESKONE^NO MALAQ (x) S^ITAETSQ WELI^INOJ BOLEE WYSOKOGO PO- RQDKA MALOSTI PO SRAWNENI@ S (x): w DANNOM SLU^AE B.M.W. (x) STRE- MITSQ K NUL@ "BYSTREE", ^EM (x):
2. pREDEL OTNO[ENIQ (x) K (x) RAWEN BESKONE^NOSTI
lim (x) = 1
x!x0 (x)
TOGDA BESKONE^NO MALAQ (x) S^ITAETSQ WELI^INOJ NIZ[EGO PORQDKA MA- LOSTI PO SRAWNENI@ S (x): (mOVNO SKAZATX,^TO : B.M.W. (x) WYS[EGO PORQDKA MALOSTI, ^EM B.M.W. (x)).
13
3. pREDEL OTNO[ENIQ (x) K (x) RAWEN POSTOQNNOMU ^ISLU, OTLI^- NOMU OT NULQ
lim (x) = C
x!x0 (x)
TOGDA BESKONE^NO MALYE (x) I (x) S^ITA@TSQ WELI^INAMI ODNOGO PORQDKA MALOSTI.
w ^ASTNOSTI, ESLI C=1, TO (x) I (x) NAZYWA@TSQ \KWIWALENTNYMI.
dLQ BOLEE TO^NOJ SRAWNITELXNOJ HARAKTERISTIKI POWEDENIQ B.M.W. ISPOLXZUETSQ ^ISLO { PORQDOK MALOSTI ODNOJ WELI^INY OTNOSITELX-
NO DRUGOJ:
4. bESKONE^NO MALAQ WELI^INA (x) NAZYWAETSQ BESKONE^NO MALOJ WELI^INOJ k { GO PORQDKA MALOSTI OTNOSITELXNO BESKONE^NO MALOJ WE- LI^INY (x) ESLI (x) I BUDUT WELI^INAMI ODNOGO PORQDKA,
T.E. |
(x) |
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k(x) |
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~ISLO k POKAZYWAET, W KAKU@ STEPENX NADO WOZWESTI B.M.W. (x) ^TOBY ONA STALA TAKOJ VE MALOJ, KAK I B.M.W. (x): ~A]E WSEGO W KA^ESTWE OS- NOWNOJ WELI^INY, OTNOSITELXNO KOTOROJ OPREDELQETSQ PORQDOK DRUGIH B.M.W., ISPOLXZUETSQ B.M.W. x ! 0:
1.2.6. |KWIWALENTNYE BESKONE^NO MALYE WELI^INY
bESKONE^NO MALYE WELI^INY (x) I (x) NAZYWA@TSQ \KWIWALENTNYMI, ESLI PREDEL IH OTNO[ENIQ RAWEN EDINICE
lim |
(x) |
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= |
(x) |
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x!x0 |
(x) |
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oTMETIM OSNOWNYE SWOJSTWA, \KWIWALENTNYH B.M.W.
1. pREDEL OTNO[ENIQ DWUH B.M.W. RAWEN PREDELU OTNO[ENIQ \KWIWALENT-
NYH IM B.M.W. T.E. |
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ESLI (x) |
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TO lim |
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x!x0 |
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dANNOE SWOJSTWO [IROKO PRIMENQETSQ PRI RASKRYTII NEOPREDELENNOS- TI WIDA 00! KOGDA ODNU BESKONE^NO MALU@, ILI OBE ZAMENQ@T BOLEE
PROSTYMI \KWIWALENTNYMI IM WELI^INAMI. pRI \TOM POLXZU@TSQ TAB- LICEJ \KWIWALENTNYH B.M.W., KOTORAQ W BOLX[INSTWE SLU^AEW POLU^AET- SQ IZ FORMUL DWUH ZAME^ATELXNYH PREDELOW I SLEDSTWIJ IZ NIH.
z A M E ^ A N I E. dLQ POSTROENIQ BESKONE^NO MALOJ WELI^INY, \K- WIWALENTNOJ SUMME, PROIZWEDENI@ ILI OTNO[ENI@ BESKONE^NO MALYH, TABLICY WPOLNE DOSTATO^NO. tAK,
sin x + x x + x = 2x |
2 |
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(1 ; cos 3x) tg5x |
(3x) |
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5x = |
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ln(1 + 3x3 + 5x) ; x 3x2 |
+ 5x ; x = 3x2 + 4x 4x: |
dLQ BESKONE^NO MALOJ WIDA MNOGO^LENA PRI x ! 0 \KWIWALENTOM SLU- |
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VIT MLAD[AQ STEPENX MNOGO^LENA |
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3x3 + 5x2 +27x x (3x2 + 5x + 7) |
7x TAK KAK PRI x ! 0 |
WYRAVENIE 3x + 5x + 7 ! 7: |
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pRI POSTROENII \KWIWALENTA RAZNOSTI BESKONE^NO MALYH PRIWEDENNOJ TABLICY ^ASTO BYWAET NEDOSTATO^NO.
tABLICA \KWIWALENTNYH BESKONE^NO MALYH
1: sin (x) (x) |
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6: |
ln [1 + (x)] (x) |
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2: arcsin (x) |
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7: |
loga [1 + (x)] |
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1 |
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ln a |
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3: tg (x) (x) |
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8: e (x) ; 1 (x) |
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4: arctg (x) (x) |
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a (x) ; 1 (x) ln a |
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5: 1 ; cos (x) |
2(x) |
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n |
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(x) |
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q1 + (x) ; 1 |
n |
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2. rAZNOSTX DWUH \KWIWALENTNYH BESKONE^NO MALYH WELI^IN ESTX WELI^I- NA BOLEE WYSOKOGO PORQDKA MALOSTI PO SRAWNENI@ S KAVDOJ IZ NIH.
~ISLO "0" NI PRI KAKIH OBSTOQTELXSTWAH NE MOVET SLUVITX \KWIWA- LENTOM BESKONE^NO MALOJ WELI^INY. pRAWYE ^ASTI ZAPISANNYH W TAB- LICE FORMUL WOWSE NE QWLQ@TSQ DOSTATO^NYMI I IH WSEGDA MOVNO DO- POLNITX, PRI NEOBHODIMOSTI, BOLEE WYSOKIMI STEPENQMI x, SWOIMI DLQ KAVDOGO PUNKTA TABLICY.
tAK, NAPRIMER, PRI x ! 0 |
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sin 3x ; 5x |
3x ; 5x = ;2x |
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ln(1 + x) ; tg5x x ; 5x = ;4x |
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p |
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4x3 |
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x |
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3x: |
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1 + 4x3 |
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1 |
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sin 2x |
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2x |
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2x = |
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w PRIWEDENNYH SLU^AQH TABLI^NYH SOOTNO[ENIJ DOSTATO^NO.
nO ESLI DWE B.M.W. \KWIWALENTNY ODNOJ I TOJ VE WELI^INE, NAPRIMER x, (\TO ZNA^IT, ^TO ONI \KWIWALENTNY DRUG DRUGU), TO PRI SOSTAWLENII IH RAZNOSTI NELXZQ KAVDU@ ZAMENITX NA TABLI^NU@ \KWIWALENTNU@, TAK KAK MOVET POLU^ITXSQ 0 :
sin x ; x x |
; x = 0 { NE WERNO, |
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ln(1 + 3x) ; sin 2x ; tgx 3x ; 2x |
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w TAKIH SITUACIQH NEOBHODIMO PRIWLEKATX DLQ POSTROENIQ \KWIWA- |
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LENTNYH BOLEE WYSOKIE STEPENI x |
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x3 |
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x3 |
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x3 |
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sin x ; x 0x ; 6 |
1 |
; x = 6 |
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sin x ; x 6 |
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0x + |
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1 |
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1 |
x |
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tgx ; sin x |
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; 0x + 6 |
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;! tgx ; sin x |
2 |
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w NASTOQ]EM POSOBII MY NE BUDEM PRIWODITX DRUGOJ, BOLEE POLNOJ,
TABLICY \KWIWALENTNYH. w DALXNEJ[EM W TEORII RQDOW BUDET RASSMOT- REN WOPROS O PREDSTAWLENII FUNKCII BESKONE^NYM RQDOM. pOKA NEOBHO- DIMO UQSNITX, ^TO ESLI NEPOSREDSTWENNOE ISPOLXZOWANIE PRIWEDENNOJ TABLICY PRIWODIT K TOMU, ^TO W KA^ESTWE \KWIWALENTA RAZNOSTI BES- KONE^NO MALYH MY POLU^AEM ^ISLO 0, SLEDUET STROITX \KWIWALENTNYE DRUGIM SPOSOBOM.
16
1.3.wY^ISLENIE PREDELOW. rASKRYTIE NEOPREDELENNOSTEJ
pRI WY^ISLENII PREDELOW NEOBHODIMO PREVDE WSEGO W WYRAVENIE, STO- Q]EE POD ZNAKOM PREDELA, WMESTO PEREMENNOJ PODSTAWITX EE PREDELXNOE ZNA^ENIE. wOZMOVNY DWE SITUACII:
1)w REZULXTATE PODSTANOWKI I PROWEDENIQ NEOBHODIMYH WY^ISLENIJ POLU^ILOSX OPREDELENNOE ^ISLO (W ^ASTNOSTI, NOLX ILI BESKONE^NOSTX), KOTOROE I QWLQETSQ OTWETOM.
2)w REZULXTATE PODSTANOWKI PREDELXNOGO ZNA^ENIQ PEREMENNOJ POLU- ^A@TSQ NEOPREDELENNOSTI. rAZLI^A@T SEMX WIDOW NEOPREDELENNOSTEJ:
00! |
11! |
(0 1) (1 ; 1) 11 00 10 : |
dLQ POLU^ENIQ REZULXTATA NEOBHODIMO RASKRYTX NEOPREDELENNOSTX mE- |
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TODY RASKRYTIQ NEOPREDELENNOSTEJ MY RASSMOTRIM DALEE NA PRIMERAH. |
rASSMOTRIM SNA^ALA PRIMERY, W KOTORYH NET NEOPREDELENNYH WYRA- VENIJ.
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1: |
lim |
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3x2 + 7 = |
3 |
12 + 7 = |
3 + 7 |
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10 |
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x!1 |
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5 ; 2x |
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px2 + 5 |
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lim |
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4 + 5 |
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2 sin x |
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2 sin |
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lim |
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4 ; |
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x!2 ln(1 + 3x2) |
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ln(1 + 3 |
4) |
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ln 13 |
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x3 + 1 |
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0 3 + 1 |
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1 2 |
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x + 1 |
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0 + 1 |
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4: |
lim |
2x3 + 8 |
3 |
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03 + 83 |
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x + 6 |
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5: |
xlim!;1 " |
#(x + 1) |
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4x + 5 |
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lim arctg |
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= arctg |
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(4 ; 4)4 |
(0)4 |
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= arctg (+1) = |
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7: x!;1lim px2 + 2 ; x = q(;1)2 + 2 ; (;1) = p+1 + 1 = 1:
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rASSMOTRIM PRIMERY RASKRYTIQ NEOPREDELENNOSTEJ RAZLI^NYH WIDOW.
11!
wO WSQKOJ BESKONE^NO BOLX[OJ WELI^INE, SOSTOQ]EJ IZ KOMBINACII PE- REMENNYH WELI^IN, STREMQ]IHSQ K BESKONE^NOSTI, I POSTOQNNYH SLA- GAEMYH, MOVET BYTX WYDELENY GLAWNAQ ^ASTX, DA@]AQ OSNOWNOJ WKLAD W ISHODNU@ B.B.W., I WTOROSTEPENNAQ ^ASTX.
tAK, W MNOGO^LENE |
y = 5x3 +3x2 |
;3x+6 |
PRI x ! +1 5x3 - GLAWNAQ |
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^ASTX, 3x2 ; 3x + 6 { WTOROSTEPENNAQ, TAK KAK |
5x3 |
3x2 ; 3x + 6 W |
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SILU BOLX[EJ STEPENI ^LENA |
5x3: |
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w WYRAVENII y = |
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3 |
+ 3n ; 1 |
PRI |
n ! 1 O^EWIDNO, |
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n + 2 + |
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GLAWNYM BUDET ^LEN S BOLX[EJ STEPENX@ n, T.E. |
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p3 8n3 = 2n: |
oSTALXNYE ^LENY |
{ WTOROSTEPENNYE. |
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w WYRAVENII |
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PRI n ! 1 O^E- |
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y = p5n + n2 ; p6n5 + 3n2 ; 1 |
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4 |
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WIDNO, GLAWNYM TAKVE BUDET ^LEN S BOLX[EJ STEPENX@ n T.E. ; p6n5 = |
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4 |
(5=4) |
: oSTALXNYE ^LENY |
- WTOROSTEPENNYE. |
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w WYRAVENII |
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GLAWNYJ ^LEN ( |
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3x) |
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WTOROSTEPENNYJ 2 , TAK KAK 3 |
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w WYRAVENII y = 12 x |
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TAK KAK L@BAQ POKAZATELXNAQ FUNKCIQ (S OSNOWANIEM, BOLX[IM EDINI- |
CY) RASTET GORAZDO BYSTREE, ^EM L@BAQ STEPENNAQ.
pRI NAHOVDENII PREDELOW OTNO[ENIQ BESKONE^NO BOLX[IH WELI^IN MOVNO PRENEBRE^X WTOROSTEPENNYMI ^LENAMI W ^ISLITELE I ZNAMENA- TELE, TOGDA PREDEL OTNO[ENIQ SWEDETSQ K PREDELU OTNO[ENIQ GLAWNYH ^ASTEJ \TIH WELI^IN, I WY^ISLENIE PREDELA ZNA^ITELXNO UPRO]AETSQ. pRI NAHOVDENII PREDELA RAZNOSTI DWUH BESKONE^NO BOLX[IH WELI- ^IN OPREDELQ@]IMI MOGUT OKAZATXSQ WTOROSTEPENNYE ^LENY, TAK KAK
GLAWNYE MOGUT UNI^TOVITXSQ, NAPRIMER
(n + 1)2 ; (n ; 2)2 = n2 + 2n + 1 ; n2 + 4n ; 4 = 6n ; 3
T.E. GLAWNU@ ROLX IGRAET ^LEN S PERWOJ STEPENX@ n:
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lim 5n2 + 3n + 4 |
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n!1 1 ; 7n ; 9n2 |
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n!1 ;9n2 |
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w ^ISLITELE I ZNAMENATELE MY PRENEBREGLI WSEMI ^LENAMI SO STEPENQ- MI MENX[E 2-OJ.
18
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lim 6n3 + 4n + 2 = |
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n!16n13; |
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= lim |
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lim n |
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A W ZNA- |
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w ^ISLITELE OSTAWILI GLAWNYJ ^LEN S WYS[EJ STEPENX@ 6n |
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MENATELE ;9n2: |
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lim |
3n + 2 |
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= 0: |
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w ^ISLITELE OSTAWLQEM GLAWNYJ ^LEN 3n |
A W ZNAMENATELE 7n |
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4: lim |
n pn + 2 + p16n |
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n!1 |
(9n |
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pn)p3n2 + n + 1 |
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2n2 |
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p3n |
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9p3 |
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n!1 9n |
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5: |
lim |
(2n + 1)4 |
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(n + 2)4 |
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n!1 (2n + 2)4 |
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+ (n |
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rASKRYW SKOBKI W ^ISLITELE I ZNAME- |
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NATELE S POMO]X@ FORMUL |
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(a b)4 = |
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= a4 4a3b + 6a2b2 |
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4ab3 + b4 |
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WYPI[EM TOLXKO ^LENY S WYS[EJ STE- |
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PENX@ n |
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= |
lim 16n4 |
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15n4 |
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= 15: |
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n!1 16n4 |
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n!1 17n4 |
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6: nlim |
(2n + 1)3 |
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(2n + 2)3 |
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1 ; 1! = |
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(n |
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1 ; 1 |
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= lim 8n |
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+ 12n |
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24n |
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;12n |
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1: |
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n!1 |
n3 + 3n2 |
; n3 + 9n2 |
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n!1 |
12n2 |
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w DANNOM PRIMERE, W OTLI^IE OT PREDYDU]EGO, ESLI RASKRYTX SKOB- KI W ^ISLITELE I ZNAMENATELE S POMO]X@ FORMUL
(a b)3 = a3 3a2b + 3ab2 b3
TO STAR[IE ^LENY S WYS[IMI STEPENQMI n UNI^TOVA@TSQ, TAK KAK IME@T ODINAKOWYE KO\FFICIENTY, PO\TOMU MY PRIWLEKLI ^LENY S MENX- [IMI STEPENQMI.
19
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7: |
lim 3 2n ; 7 6n |
= |
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! |
= lim |
;7 6n |
= |
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n!1 2 6n + 5 2n |
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n!1 |
2 6n |
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gLAWNYMI ^LENAMI ^ISLITELQ I ZNAMENATELQ QWLQ@TSQ SLAGAEMYE S BOLX[IM OSNOWANIEM STEPENI, T.E. 6n.
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8: lim |
5n+2 |
; 8 3n;1 |
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= lim |
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5n 52 |
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n!1 |
4 |
5n;1 |
+ 21 |
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1 |
n!1 4 |
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5;1 |
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2 |
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125 |
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4 5;1 |
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gLAWNYMI ^LENAMI ^ISLITELQ I ZNAMENATELQ QWLQ@TSQ SLAGAEMYE S BOLX[IM OSNOWANIEM STEPENI, T.E. 5n, WYRAVENIQ c POKAZATELQMI STE-
PENI (n + 2) I (n ; |
1) NEOBHODIMO SWESTI K WYRAVENIQM, SODERVA]IM |
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TOLXKO STEPENI n |
^TOBY OPREDELITX KO\FFICIENTY PRI 5n: |
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tO ESTX |
n+2 |
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2 |
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= 5 5 |
5 ; = 5 5; |
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: 5 |
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9: |
lim 1 + 3 + 5 + ::: + 2n ; 1 |
= |
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n!1 |
(2n + 5) |
(3n ; 1) |
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wYRAVENIE, STOQ]EE W ^ISLITELE DROBI, PREDSTAWLQET SOBOJ SUMMU n ^LENOW ARIFMETI^ESKOJ PROGRESSII, KOTORU@ MOVNO NAJTI PO IZWEST-
NOJ FORMULE
Sn = (a1 +2an) n:
w NA[EM SLU^AE a1 = 1 an = 2n ; 1 ^ISLO ^LENOW PRORESSII n: u^I- TYWAQ \TO, I, OSTAWLQQ W ZNAMENATELE TOLXKO STAR[IE ^LENY, POLU^IM
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(1 + 2n ; 1) n |
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(2n) n |
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lim |
2 |
= lim |
2 |
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n!1 |
(2n) (3n) |
n!1 |
(2n) (3n) |
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10: nlim |
1 + 2 + 4 + 8 + ::: + 2n |
1! : |
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2n+3 + n2 |
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!1 |
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1 |
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= lim |
n2 |
= |
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: |
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n!1 6n2 |
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6 |
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wYRAVENIE, STOQ]EE W ^ISLITELE DROBI, PREDSTAWLQET SOBOJ SUMMU n ^LENOW GEOMETRI^ESKOJ PROGRESSII, KOTORU@ MOVNO NAJTI PO IZWESTNOJ FORMULE
Sn = a1 (1 |
; qn) |
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1 |
; q |
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20 |
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W NA[EM SLU^AE a1 = 1 q = 2: tOGDA POLU^AEM
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lim |
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1 (1 ; |
2n) |
= lim |
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1 ; 2n |
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n!1 (1 ; 2)(2n+3 + n2) |
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n!1 (;1)(2n+3 + n2) |
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oSTAWLQEM TOLXKO GLAWNYE ^LENY |
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lim |
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= lim |
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2n |
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n!1 |
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n!1 2n 23 |
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23 |
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1 + |
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+ 9 |
+ ::: + |
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1 |
! |
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11: nlim |
3n |
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= |
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1 |
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1 |
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!1 |
1 + |
+ |
+ ::: + |
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1 |
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5 |
25 |
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5n |
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= lim |
1 "1 ; 31 |
!n# |
1 |
; 51 |
! |
= lim |
"1 ; 31 |
!n# |
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n |
# 1 ; 31 |
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"1 ; 51 |
n |
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n!1 1 "1 ; 51 |
! |
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! |
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n!1 |
! |
# |
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6 |
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1 ; |
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31!n |
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6 |
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51!n = |
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45! =
23!
wYRAVENIQ, STOQ]IE W ^ISLITELE I ZNAMENATELE DROBI, PREDSTAWLQ- @T SOBOJ SUMMU n ^LENOW GEOMETRI^ESKOJ PROGRESSII, KOTORU@ MOVNO NAJTI PO PRIWEDENNOJ WY[E FORMULE.
w ^ISLITELE a1 = 1 |
q = 1=3 W ZNAMENATELE a1 |
= 1 q = 1=5: dALEE |
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U^ITYWAEM, ^TO PRI n |
! 1 WELI^INY (1=3)n I |
(1=5)n QWLQ@TSQ BES- |
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KONE^NO MALYMI, T.E. STREMQTSQ K NUL@. |
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n!1 (n + 1)! ; n! |
1 |
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sIMWOL n! |
( n; FAKTORIAL) |
ESTX KRATKAQ ZAPISX PROIZWEDENIQ NATU- |
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RALXNYH ^ISEL OT 1 DO n WKL@^ITELXNO, T.E. |
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n! = 1 2 3 4 (n ; 1) n:
nAPRIMER, 3! = 1 2 3 = 6 5! = 1 2 3 4 5 = 120:
21
dLQ RE[ENIQ PRIMEROW POLEZNO ISPOLXZOWATX SLEDU@]IE SOOTNO[ENIQ
(n + 1)! = 1 2 3 4 n (n + 1) = n! (n + 1) n! = 1 2 3 4 (n ; 1) n = (n ; 1)! n
(n + 2)! = 1 2 3 4 n (n + 1) (n + 2) =
= n! (n + 1)(n + 2) = (n + 1)! (n + 2) = (n ; 1)! n(n + 1)(n + 2):
w DANNOM PRIMERE ISPOLXZUEM (n + 1)! = n!(n + 1) WYNOSIM W ZNAMENA- TELE n! ZA SKOBKI, SOKRA]AEM S n! W ^ISLITELE. tOGDA
lim |
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1 |
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1 = 0: |
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n!1 n![(n + 1) ; 1] |
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(2n + 2)! ; (2n)! |
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n!1 5(2n + 2)! ; 3(2n + 1)! |
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1 |
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iSPOLXZUEM SLEDU@]IE SOOTNO[ENIQ |
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(2n)! = 1 |
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3 (2n ; |
1)(2n): |
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(2n + 1)!=1 |
2 (2n |
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1)(2n)(2n + 1)=(2n)!(2n + 1): |
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(2n + 2)! = (2n)!(2n + 1)(2n + 2): |
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lim |
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(2n)!(2n + 1)(2n + 2) |
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(2n)! |
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n!1 5(2n)!(2n + 1)(2n + 2) ; 3(2n)!(2n + 1) |
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= lim |
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(2n)![(2n + 1)(2n + 2) |
; 1] |
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n!1 (2n)![5(2n + 1)(2n + 2) |
; 3(2n + 1)] |
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= lim |
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(2n + 1)(2n + 2) ; |
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= lim |
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2n 2n |
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n!1 5(2n + 1)(2n + 2) ; 3(2n + 1) |
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n!1 5 2n 2n |
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5 |
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dO SIH POR MY RASSMATRIWALI PRIMERY WY^ISLENIQ PREDELA ^ISLO- WOJ POSLEDOWATELXNOSTI, W KOTORYH PEREMENNAQ WELI^INA n PRINIMAET TOLXKO CELYE POLOVITELXNYE ZNA^ENIQ (T.E. n ! +1). pRI WY^ISLE- NII PREDELA FUNKCII NEPRERYWNOGO ARGUMENTA x WYRAVENIE x ! 1 SLEDUET PONIMATX KAK DWA:
x ! ;1 I x ! +1: w TEH PRIMERAH, GDE REZULXTAT WY^ISLENIQ PRE- DELA NE BUDET ZAWISETX OT TOGO, STREMITSQ x K ;1 ILI K +1 MOVNO ISPOLXZOWATX SIMWOL x ! 1 A W PRIMERAH, GDE REZULXTAT WY^ISLENIQ PREDELA OKAZYWAETSQ ZAWISQ]IM OT TOGO, K POLOVITELXNOJ ILI OTRICA-
TELXNOJ BESKONE^NOSTI STREMITSQ x SLEDUET WY^ISLQTX PREDELY x!;1lim