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Popov et al - Collected Problems in Theoretical Mechanics from Olympics (Tambov University, 2002)
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. . , . . , . . , . .
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"" , , ! , , , ! . , !
( - )
. . , . . , . . , . .
,
1
2002 1273-4 531(075): 378.14 -58
:
. . ,
. .
. ., . ., . ., . . -58 . 1. . 2- ., . . : -
. . . -, 2002. 80 .
180 , 1981 1990 , . , . .
, .
1273-4 531(075): 378.14
(), 2002
. ., . ., . ., . ., 2002
, , ,
. . . .
020851 13.01.94 020079 28.04.97
27.04.2002 60 84/16. . . Times. : 4,65 . . .; 4,38 .-. .
150 . . 322.
-
392000, . , . , 106, . 14
, , , - . , , . , .
, . (, 1992 - 1995; , 1996 - 2001), (, 2000 - 2001), , .
C1 (, 1982. 3 ) , -
, , . , f.
2 (, 1982. 3 )
, . 1 M . , , - , . 2 1.
(, 1983. 3 )
, . - , , Q, , . .
C4 (, 1983. 10 )
OABD Q
, B . . , , , . .
5 (, 1984. 5 ) 1 M1. 2 , 3
, 21O = 90, O1O2A = , O1A = r, CO2 = O2D = a, 2 3 f, 1, , 2 , , 2 3 D.
6 (, 1984. 4 )
, - , - - , - . f, l, a . -.
7 (, 1985. 4 )
OA O, KL. - - l. - , - - f. M , - . .
8 (, 1985. 8 )
. , , .
,
F = M SK/(LK OS), AS AE, EC OC, AE || OC.
l
9 (, 1986. 3 )
S , -, .
10 (CCP, 1986. 4 )
1 Q1 Q2, . f. f0 2 3 .
11* (, 1986. 4 )
m1 m2, A1x + B1y + C1z + D1 = 0 A2x + B2y + C2z + D2 = 0 . .
C12* (, 1986. 3 )
M1 2 - , - . . - , M2 1.
* , , .
C13 (, 1987. 5 )
- z = H - (x2+y2)/H. h . h - , f ?
C14 (, 1987. 6 )
Q R , ,
F
H
, D. d , . , f, tg > /R, f > /R. ?
C15* (, 1987. 4 )
R r, - , - c. , Q. , ?
C16* (, 1987. 7 )
,
M0 = MA = MB = m. V z; = a, = b. , - M0 , MA , MB .
C17 (, 1988. 10 )
l O - h - , . , k (k - ). . .
C18 (, 1988. 4 )
R - , . ( ) . AA1 1 , -.
19* (, 1988. 5 )
AB = l Y, Z YZ. , F, .
20 (, 1989. 6 )
- P1 2. , - f1. f2.
z
x
. F ?
C21 (, 1989. 4 )
. - - , M, Z, F. F 1CY1 (X1 // X, Y1 // Y) Y1 = 60. - , = , = , = . = 1 , = 2 , = 0,5 , F = 2 H, = 0,5 H, M = 1 .
22* (, 1989. 5 )
12 1 = 2 = , = 12 = ( > ). - 1 2,
1 2. - 2/1, O2 12.
23 (, 1990. 4 )
. -. . , f. . f ?
24 (, 1990. 5 )
- - - D . D . - , - . - ?
25 (, 1982. 3 )
, - , . , ?
26 (, 1982. 3 )
, 1 2 (1 > P2) - l, r = 0,5 2 l,
- f. , . .
27 (, 1983. 5 )
M2, , , D 5. . : = = l, CD = 0,5l, = 60, = 90; .
28 (,1983. 3 )
,
, Q, f0. - = f(y), .
29 (, 1984. 5 )
- - . , - , : R, Q f, (OA = AB = R).
30 (, 1984. 5 )
DOE. , Q, M, = = l.
C31 (PCP, 1985. 3 )
2R , . .
32 (, 1985. 3 )
, - -, - , - . , F, - . R .
33 (, 1986. 3 )
D . -
1 . - l, = = 0,5l; , CF, P
r BD.
34 (, 1986. 5 )
c 1,
= 600 c? h = 1 . A f = 0,3, . : r = 10 , a = 4 , b = l = 20 , = 90, = 45.
35 (, 1987. 3 )
G - - . f , . - Pmin, , - .
36 (,1987. 5 )
. D 90. r, f0 = 0,268. 0B0, . : 1) B , 2) l
. : f, = 4, tg = f, M = b G, h = 3/2 f b.
38 (PC, 1988. 5 )
- , - - . - - . - f - . NA, , , -.
39 (, 1989. 3 )
2 Q r
- O1O2 2r O1; 1 3. ; O1A
. 3.
40 (, 1989. 5 )
- , - . . : = = l, r1 = R2 = 0,5l, r2 = 0,25l, = 30, = 90, 3 = 0, QA = QB = Q.
C41 (, 1990. 3 )
2 G2 r 1 G1 , O. - -. L, O - l, - f. , , f, G1, G2 .
42 (, 1990. 3 )
- c , . : - - r/R = 0,2, - = 30 f = 0,577, k/R = 0,5, Q, O - .
43 (. , 1984. 3 )
-
l
l/3
V1=const
l l
1
2
3
3
, - - l/3. . .
44 (. , 1984, 3 )
OBAD OZ O D. OZ . ZOZ1. - , Q, . 2 2b (AD = 2a, OD = 2b) , O D.
45 (. CP, 1987)
( ), F? .
46 (, 1983. 3 )
, - , r. r - , l. l , , .
47 (, 1985. 3 )
1 2 m1 m2, , , . - f. - - . 48 (, 1986. 3 )
O, ,
: MO = , MA = 4M, MB = 5M. , , .
49 (, 1982)
, n , - -. - ; Q - ; O, 1, 2, ... n - . k ( = 1, 2, ..., n) .
50 (, 1982)
1 2
n
C. f1 f2 (f1 < f2). , -, MN.
51 (, 1987)
O O A . , -
. - Z.
52 (, 1982)
. r h . - f. b - , - ? - .
53 (, 1983)
, 1 (1X, 1Y, 1Z) 2 (2X, 2Y, 2Z), 1 (1,1,1), 2 (2,2,2), .
54 (, 1984)
, -, M l , - . D B . . c , 2l 2 .
C55 (, 1984)
, D , , , D . - 1, 1, D1 , . , - .
56 (, 1985)
MO, MA MB - - - , , ; OM = 3 Fh k ; AM
= 3 Fh k ; MB = 5Fh; OA = OB = h. .
57 (., 1985, 3 )
4 - - D G, D - , G - . M Q. , = AD = DC = , F = 2.
58 (. , 1983, 3 )
- -, - ,
. , - , 1-1.
, - 1-1, .
59 (., 1988)
G, r R
. f , = 30 r/R = 0,2.
60 (. , 1985, 3 )
- 1 2 - h -. - - . - - f.
61 (. , 1987)
G , - ; - f. , , = , .
62 (. , 1988)
D B1 - 1 DD1. B1 D, D = 1D1 = 1/3 1. .
63 (. , 1983. 3 )
- . - M, 1 r , 1O = /2, 1 = /6, = = 2 3 r.
64 (. . 1984, 3 )
,
, ,
. f, . x = D, , n ? .
65 (. , 1988)
l = 4 y = 0,5 x2. -.
66 (. , 1988)
AB D . D , Q. , = 4 ; = 12 H; Q = 16; a = 1 . 67 (. , 1986. 3 )
D, , 5, 6, 7, 8, 9. L Q Z 1, 2, 3, 4. 1 2, -, = 8 ; Q = 6 ; = 4 , = 3 , = b = = 2 ; L = 5 ; = 2 ; = = = 45; KL OY.
2 2
Z
1 2
3 4
5
6
7
9 8
Y
X
68 (, 1985. 3 ) , , , .
, , . ? .
69 (, 1986. 3 )
m . l. - - 1, - 2. .
70 (, 1986. 3 )
, ? = 2.
71 (, 1988)
M , x = x0 y = sin (x) Q, . , f < (dy/dx) (x0).
C72 (., 1984. 3 )
OX Q , F1, F2, F3, Q ? F1 = = F2 = F3 = F.
73(., 1984. 3 )
R P, ,
- ( f). - F - - h, ?
74 (., 1985. 3 )
1 2. 1 . 2 , . f 2 , 1 ? , 2 .
75 (., 1986. 3 )
, , . - , R1 R2 - , , yi : Ri = R0 + k0 yi, R0 k0 - . 0 l0. .
76 (., 1986. 3 )
, - , - , - -
P
. = 12,0 . , DF . .
77 (., 1987) - O
- - . , , - , .
78 (., 1982)
, n ,
, - - . l. .
79 (., 1983)
: F1, F2, F3, , , D .
= = b 120 ? F1 = F2 = F3 = P, AB = OC = OD = a.
80 (., 1982)
n , . 1, 11 / 11 = = 22/22 = ... = nn/nn = 1/4.
81 (., 1963)
: 1Pr
= P kr
, 2Pr
= P ir
, 3Pr
= P jr
, 1(, 0, 0), 2(0, , 0), 3(0, 0, ), . - , , ?
82 (., 1984)
, .
L ( n ), n .
83 (., 1985)
, - - f. - 45 -. - ( x), . 2. f x , ?
84 (., 1985)
- .
85 (., 1977)
a Q M , M l. r (r = ), 2/
91 (.-. , . - / ., 1990)
Q ,
G,
. , , .
92 (.-. , . - / ., 1990)
, - - . , . 1 , .
93 (. , 1979)
1 . ,
2 3 f , , .
94 (, 1987) = , D = 2 ,
, D. , F - , - .
95 (, 1986)
2Q r
l D. ? - . ; - -.
96 (, 1987)
- . - , ?
97 (, 1985)
, , O1 = O1O2, 1 2 P1 P2 -.
, , , 1 = , BO2 = 90, , 1 2 .
G
1
2
98 (. . -, 1982)
A 1, M2, M3, M4,
YOZ, ZOX, XOY , . , 1 = 4 ; 2 = 3 ; 3 = 1 ; 4 = 3 ; = = .
99 (. . -, 1983)
-
2h .
, - h. f 0,6. ? . 100 (. . -, 1984)
Q D, -
, . - f. - ? - , Q, f, ( - -). 101 (c. .-. ., 1987)
R r ,
. . . , . , r 0 0 (.. , ). . , r - , r ; r R 0. ? )(tg r R 0. ? , 0 < r < . , , ( ).
102 (. - . ., 1987)
2l R. , , .
103 (. . -, 1986)
R
Q . - f = 0,5. , , = 2 = 2 R ? .
104 (. -. -, 1978)
l Q - . a . , YOZ . B f. .
105 (, 1982)
. 0,3, N. , , 0,25N ?
106 (, 1980)
aaa 2 , 12, . 12 D C A, , . , . .
107 (, 1986)
h , ? f = 0,2; 2 .
108 (, 1979)
- - . P1 2 r1 r2 .
. , . .
109 (, 1979)
- , - .
, , . , . f, = = a.
110 (, 1981)
, , , . . , ?
111 (, 1980)
. 2l Q, . Q0 , , . l, . .
112 (, 1978)
, D. . ( ). - . 11 (, 1978)
. f. f ? Q,
. Q ?
114 (. 1978)
, , 1, , 2 R, ( ) fA fB , , . , .
115 (. . -, 1982)
, , ,
60 . D Q. Q, , f. . 116 (. . -, 1982)
, , , D, - . - - - 45. B , = 4 . 117 (. . -, 1983)
R
,
l = 2r, 1 r, . 2. Q, ; b = r, - f ; 2; . 118 (. . -, 1982)
, , 1 2 G . Q ,
. .
119 (. . -, 1983)
r
G R; Q , . Q ?
120 (. . -, 1984)
m = 500 .
: - 1 = 0,01 , - 2 =
0,005 . - f = 0,1. , , . 121 (. - . ., 1985)
, ,
Q, ? ( ) f, R .
122 (. - . ., 1983)
. . , 1.
123 (. - . ., 1987)
R. . , , , Q. Q , ? f,
0,8
Q
. 124 (. - . ., 1987)
BED O
D P R. = 60o , = 30 . , . f1 f2, . .
125 (. - . ., 1984)
m1. m2, O1B , , = 90, = 30, = O1 = l. . F, ? = l 2 , AK = l. . 126 (. - . - ., 1985)
O, , , , D, - . . D m. - O, D = , = . D F, ? 127 (. - . ., 1987)
BE D . E - , , - D P. yA, xD; = 20 ; m1 = m2 = = 120 . , , .
128 (. - . ., 1988)
m l ABCD, 1 C2; - . , . , . 129 (. - . ., 1988)
D
, , . -
1 , , D .
130 (. - . ., 1989)
6 , Fi, .
131 (. - . ., 1989)
R . M OZ, O, , f ?
132 (. - . ., 1989)
Q r. - . , P =
81 Q.
, min ? min min . 133 (. - . ., 1989)
O1A O2B R r . - , Q, p. , . -. 134 (. - . - ., 1989)
R , , . r . . .
135 (. - . ., 1989)
, . - ,
, 1 = 1,5 , 2 = 1 , P3 = 2 , , .
136 (. - . ., 1989)
2Q r, , . , , . , , . , . .
137 (. - . ., 1988)
F Q. F . Q, .
138 (. . -., 1987)
, 30=
f = 0,15? . - - = 0? 139 (. . -, 1986)
D
- . -, .
140 (. . -, 1986)
r
. . R.
C141 (. . -, 1986)
R
- r ? f. . 142 (. . -, 1985)
1 1 ,
, R. f, r = R/2. P2 - 2 ? 143 (. . -, 1985)
h ,
, 10, ? : f - ; - - . 144 (. . -, 1985)
, f = 0,2? . ? , ?
145 (. . -, 1987)
, , , . . - -. . -, .
146 (. . -, 1983)
= = b . , , . . - .
147** (, 1992. 4 )
AB = l P
B f < 1, . , D. , . , , P = 2cl.
** 147 - 154 .
. . , . . , . . , . . . 148** (, 1992. 3 )
Q
. , . FGHN ,
B
D A
30
N
HP1
P2
G
BF
AE
. NH, . , , AF = 105 AEAB = .
C149** (, 1993. 5 )
, , , 0. : 1) f , , ; 2) , , . . 150** (, 1993. 4 )
ADBE P AB = DE = 2l - .
, : 1) - - ; 2) , D
25Pl . , .
151** (, 1994. 5 )
, , , , - , . P1 = 1 , P2 = 2 . A , f1 =0,2, f2 = 0,15. = 60.
, , .
152** (, 1994. 3 )
a b AD, BF, CH. , x, y ,
x. , ab 2/tg = .
X
a
H
CD
z
O bB
y
F
A
153** (, 1995. 4 )
P r . B f = 153 .
A B
= 60o. BD 8r, . F = 2P. ? ?
154** (, 1995. 4 )
ABCDEH AB = CD = 4l AE = DE = l AED = 2 EG. , EG . . , AD = 15o .
155*** (, 1996. 3 )
, n , . , Q, . ( > Qsin). ,
. .
n
n-11
Q
1 n-1
n
*** 155 - 166 . . . , . . , . . . 156*** (, 1996. 4 )
, - . D. , , f. 157*** (, 1997. 3 )
. , ?
158*** (. 1997. )
-
, . - 2 . , , f?
159*** (, 1998. 5 )
AD
B
: l, 2l, 2,
. , . , , = l ( - ). 160*** (, 1998. 6 )
l , .
, ( < l). f. l ? 161*** (, 1999. 3 )
,
b, Q . ,
. , .
162*** (, 1999. 5 )
, , . , l, , r. Q = 2. , f, .
C163*** (, 2000. 5 )
2r r r. , . .
C164*** (, 2000. 5 )
. xAy f, z. xAz. f 30? ,
A
B Q
, A .
165*** (, 2001. 5 )
R , . , f (f < 1). .
166*** (, 2001. 6 ) a, b Q f. ,
)2/0( ? .
C 167**** (, , 2000. 3 )*
n mk xk, yk, zk, k = 1 n. Q: kF =f mk QM k , f - . Q, , .
168**** (, , 2000. 4 )
2P , . f. - , 45 . ( x). , f x , ?
**** 167 - 170 . . . , . . , .
. . 169**** ( - , , 2001. 6 )
,
() D. OD DA, . = 2l.
170**** ( - , , 2001. 6 )
m . . .
171**** (, 1992. 4 )
ABCD, , , . BC CD --, . = BD = b, .
172 (, 1992. 6 )
-- (
), = = r. m = M 3 , F, .
173 (, 1993. 4 )
SABC P , , . , . S F, , ? . 174 (, 1993. 6 )
1, 2,
3, 4 F, Q. F CD , Q DE CK; BD = DC = BC = a; CK = CN. Q . .
30
F
175 (, 1995. 4 )
1 2 , f. , . 2. 1 .
176 (, 1995. 3 )
BD 1 2
, = l, BD = 1,5l, AE = EC = CK = KB ACB = 60. f. Q D, , ? S .
177 (, 1995. 5 )
= 4 , , - , - . CD KL . 1 z, 2 30. 2 F = 2 , , - m , ON m = 2 a , - . OA = OB = = AN = BE = AD = OK = OC = a (), KL - z KL OL, OL || AN. (-) CD KL.
178 (, 1996. 4 )
r
R, . ,
. R, .
179 (, 1996. 3 )
F
.,,, 4321 MMMM , .5,1,2, 21 lCDlBOlAO === 4M .
180 ( , 1993. 5 )
1 R Q, 2 , . , 2 f. P 2, 1?
178.
1:
30
1
2
====+=
===
.3
;030cos30cos,0
.;060cos60cos,0
12121
2121
NPNNPNNY
NNNNX
oo
oo
2: ( ) 060coscossin,0 131 =+= oNNPX .
( )( ) .3,6721
sin;
147sin
,93tg060cos
3sin
.03
rrrrR
PP
N
+=+==
==+
=
o
: R < 6,3r.
179.
:
.0
.0
44332211 =+++=
DSFMMMM
A
AB - , .03 =
() CD D,
.05,12
;23,2,
.0
421
421
=+
===
====
lSM
lSM
lSM
lSlSlS
SSSS
S
CBA
CBA
D
180.
( ).243: 124 MMM =
:
;02;0 1 == RFNMmC
.2
02;, 1 fRQMPRPfQMPfFQN ====
.0;0;0 111 QPffPfQfFFx ===
: fRQMP 2/)( = , QPff /1
1. f 2/tg . 2. )/()cos( 2 caM = . 3. )2/( QPQf + . 4. 2/tg)( += QPYa . 5. )cossin/()( 21min2 += fraaMM . 6. )1(3,3max fal += . 7. )cos)sin/((cos)( += fPlM .
8. , L - , S - , - . 9. 2/PS = . 10. .arctg2max f= )/( 211min QQfQfO += . 11.
222111 // RAmRAmmX += ; 222111 // RBmRBmmY += ; 222111 // RCmRCmmZ += , 2121211 CBAR ++= ; 22
22
222 CBAR ++= . , m1 m2
(). 12. )9/3(arctg= . 13. )4/1( 2fHh . 14. )/cos(sin/)/cos(sin RDQPdRDQ +
32. RMF /3= . 33. 2/31 PlM = . 34. /210min =C , H20min =P . 35. )arctg2cos(min fGP += . 36. 1 : ) o450 ; ) 00 . 2 : ) 045 . 51.
0RM Orr
- , hMMR OAXZ /22 += .
52. 291/6 fRfb + , 224/4 haRab + . 53. ))(())(( 22221111212222111121 ZXZXYYYZYZXX PaPcPaPcPPPcPbPcPbPP +++++ 0))(( 111121 =++ ZYZZ PbPaPP . 54. lmgc /2= . 55. 6/MgT = . 56. FR 4= . 57. 2/ctg)2(23 += QPx A , 2/ctg)2(2 += QPyA , QzA = , += sin/)2( QPTCG ,
+= ctg)2(2 QPT DE . 58. 3/3f . 59. 4,0min =f . 60. fha 2/min = , 0min P . 61. )cos2/(sincosmin += fGP , )cos2/(sincosmax = fGP 62. PS E 4,2= , PS D 1,2= , PyA 3,1= , Py B 2,1= , P AD. 63. Pr75,0min =M . 64. )1/()()1/()( 2222 ++ nbfanxnbfan , 1>n , 1222 += nnfab . 65.
o451 = , o1352 = . 66. 0=Ax , 14=Ay , H32=AM , H2=CR . 67. 24,021 == SS . 68. ( M , , , M ). 69. )(/)( 2112 += PmgPlx . 70. 9min =n . 71. + cossin/cossin fPQf , 0tg x= . 72. FQX 5,1= . 73. ))/()2(( hRhRhfPF + . 74. = tgf . 75. 21
2021001 2))(2( ylPyykRy =++ , 2122012200 )()))(( yylPyyykR =+ . 76. 2,17== AB xx , 3=Ay ,
9=By , 6=CN , 5,89=CM . 77. 0)sin()sin( >+ . 78. )/1/())/(1(5,0 lalaPy nA = . 79. 2/2ab = . 80. 3/)4/11(2 nPT = 81. 0=++ cba . 82.
==
n
iiaL
1)/1(2/ . 83. 1) )1/()12( flfx +> . 2) 2/,1 lxf == . 84. PxC 7= . 85. QaPar /cos422 = . 86.
bafl 2)1/tg( ++ , ftg . 87. QN 4= . 88. == BA RR 3/PRC = . 89. )cos/(sin)cos(sin ++= ffPQ . 90. ftg , cos/tg r . 91.
)cos(/(cos)2sin(costgmin ++= QGP 92. )sin5,13/()cos1(tg += , )sin2/()cos1(tg 1 += . 93. farctg2r , )(4/3tg 222 rrRRr ++= , oooo 6,18,5,0;6,53,2;67,;1,38,( ==== RrRrrRr ) 2) 0
166. )1/(8 2max fRfl += , 32 f . 167. . . 168. 2/lx = . 169. 2/Ll = . 170. )2/(tgtg MmM += . 171.
abPT = 172.
34r
MF = .
173. 3
6PF = . 174. aFaMMMQ /)2(4 431 ++= .175. P )ctg21()ctg21( 212 + fPPf . 176.
fPPQPP )(3652
2121 ++ , S = .3
232
21
+ QPP
177. 21 =S .
1 . . . . 1. -., 1980. 172 . 2 . . . .: , 1986. 448 . 3 / . . . . . .: , 1986. 480 . 4 / . . . . .: , 1983. 320 . 5 . . . .: , 1978. 189 . 6 . ., . ., . . . .: ,
1987. 176 . 7 . ., . ., . ., . . / .:
, 1980. 210 . 8 . ., . . : . . : - . .
. -, 2001. 84 . 9 . ., .. . : F, 1998. 56 . 10 1987 - 1998 /
. . . . : i, 2000. 280 . 11 . : -
, 2000. 76 . 12 " -
" 1992 . : - , 1993. 32 . 13 " -
" 1993 . : - , 1994. 26 . 14 " -
" 1994 . : - , 1995. 32 . 15 . : -
, 1996. 56 . 16 . : -
, 1997. 68 . 17 . : -
, 1998. 72 . 18 . : -
, 1999. 90 .