阳光小院暖茶 发表于 2015-5-14 13:10
1 Z2 O( W" z/ G* _0 P+ A* v8 q9 }, ~8 N不好意思,我看题目看了几遍,还不知道这个方程是咋样的。光括号就让我迷糊了。帮不了你了
2 C. w5 U& Y) U+ v$ f) Z" o9 k我用matlab 重新算了下 A1用t替换 B1用q替换 11/6 用替换 50用R2替换0 L; Z1 i& w/ T$ y8 Q0 {
>> syms t q a k A R2
( A; {4 [, A4 D+ c. X! i/ e4 J! ]>> x=R2*t*sin(t)+a( Q5 ~) d4 s' _# U9 R. f, v
; F; s% C1 T% c3 `, |8 Yx =& _, B6 C H) S5 e) _, P
C4 }+ {( ^) |$ C, d
a + R2*t*sin(t)
0 o1 A; t; Q8 A$ n) ~
$ ]( t2 k( B" f* ~; O5 J>> y=R2*t*cos(t)
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; `- m: U9 I2 P- E" Q# A- n! ]1 S3 Hy =" n% {/ z' j2 d; a
F. [& f5 K# ^! g# S7 w
R2*t*cos(t)
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3 e& F6 |' ]8 s( D% C% a>> x1=-x*cos(k*q)-y*sin(k*q)+A*cos(q)7 a9 N9 \6 P6 {3 f/ o) Y
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x1 =
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1 I$ V7 k, C- WA*cos(q) - cos(k*q)*(a + R2*t*sin(t)) - R2*t*sin(k*q)*cos(t)
6 a+ i( r. w5 W6 [7 o6 n) ]4 F: D8 J$ @ N4 U5 S9 _, o0 Q6 [# c
>> y1=-x*sin(k*q)+y*cos(k*q)+A*sin(q)) o3 u; M w3 J# j
f$ n @) W3 s. ]+ Z% c0 by1 =: N) }( K" D1 X
5 E5 O0 {$ ~- H& h- R: pA*sin(q) - sin(k*q)*(a + R2*t*sin(t)) + R2*t*cos(k*q)*cos(t)
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>> diff(x1,t)3 a1 ] Z, N( | I( ^
+ N$ T4 d/ X% M, j4 m0 Oans =
5 u/ G: y Q" N% n, k" x, V
. Y0 {0 ?# `! m0 v7 P8 m ^R2*t*sin(k*q)*sin(t) - R2*sin(k*q)*cos(t) - cos(k*q)*(R2*sin(t) + R2*t*cos(t))* T4 _! G1 O' E
" e& q+ O, x2 h8 G+ Y- e
>> diff(x1,q)( ~0 y2 k; W% u
) y5 p/ Y" b( s0 l% [
ans =3 b, W7 Q7 Q2 B3 y% c
: Q2 Q1 O( l. u1 A
k*sin(k*q)*(a + R2*t*sin(t)) - A*sin(q) - R2*k*t*cos(k*q)*cos(t)
. R% j1 k9 H- a8 ?# V
1 t6 ~; i7 J* k. C2 F! @ u6 l; k>> diff(y1,t)
9 R& S! I1 V) H* v, o4 p# k/ u/ _0 y, f9 Y% b1 |; H
ans =
. y. {! Q: v+ E+ _ k# f o: p
( j2 x2 S; H) r2 `! c5 ]. OR2*cos(k*q)*cos(t) - sin(k*q)*(R2*sin(t) + R2*t*cos(t)) - R2*t*cos(k*q)*sin(t)
0 }1 i; ?) R( t+ X; x, s
' M) ~" Q3 v. K F2 g9 M* e! I9 t>> diff(y1,q) R. }: N' W. h, Y$ {% r1 b- T
o4 |& @9 F! M) j0 g
ans =
2 }* m: c B3 p$ B* |* D v
9 h4 ?) ^, K9 s7 G/ r" E u! QA*cos(q) - k*cos(k*q)*(a + R2*t*sin(t)) - R2*k*t*sin(k*q)*cos(t)
+ ~5 d5 M2 o: [1 W/ e3 Q2 i3 O) O
& y9 r/ m3 I* N; r! g$ p>> f1=sym('(A*cos(q) - k*cos(k*q)*(a + R2*t*sin(t)) - R2*k*t*sin(k*q)*cos(t))*(R2*t*sin(k*q)*sin(t) - R2*sin(k*q)*cos(t) - cos(k*q)*(R2*sin(t) + R2*t*cos(t)))-(k*sin(k*q)*(a + R2*t*sin(t)) - A*sin(q) - R2*k*t*cos(k*q)*cos(t))*(R2*cos(k*q)*cos(t) - sin(k*q)*(R2*sin(t) + R2*t*cos(t)) - R2*t*cos(k*q)*sin(t))')' n3 @8 f& k" W# L
4 X5 C1 F5 ]" ]% k, @4 }f1 =7 K7 g3 A. L; J" ^4 A& n: X
6 ?3 u, r& t9 k1 u* Q(k*cos(k*q)*(a + R2*t*sin(t)) - A*cos(q) + R2*k*t*sin(k*q)*cos(t))*(cos(k*q)*(R2*sin(t) + R2*t*cos(t)) + R2*sin(k*q)*cos(t) - R2*t*sin(k*q)*sin(t)) - (A*sin(q) - k*sin(k*q)*(a + R2*t*sin(t)) + R2*k*t*cos(k*q)*cos(t))*(sin(k*q)*(R2*sin(t) + R2*t*cos(t)) - R2*cos(k*q)*cos(t) + R2*t*cos(k*q)*sin(t))2 i5 R+ a, X f& f( O( L l1 K
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>> simplify(f1)% q$ f/ v& x4 {2 M
% F- k* E% g+ M% N! J: `7 t
ans =
; n4 W$ b1 K, C. @; [' q F4 u: |% E+ ]$ S; w, O% w }
A*R2*sin(q - t - k*q) + R2^2*k*t + R2*a*k*sin(t) - A*R2*t*cos(q - t - k*q) + R2*a*k*t*cos(t)
3 a* r% [0 l. y, P" f5 V |+ x4 n2 o/ n& |
. E( [- B( n: h6 k* I$ [令 A*R2*sin(q - t - k*q) + R2^2*k*t + R2*a*k*sin(t) - A*R2*t*cos(q - t - k*q) + R2*a*k*t*cos(t)=0
: f8 b7 x7 h; C5 G% Q + F) y: ~* V$ u) s7 G& I2 ]4 D
则q的表达式可手算出来
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