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楼主 |
发表于 2017-7-19 22:05:01
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K = DSolve[{-V/(x*f''[x])*Sqrt[1 + f'[x]^2] == 2*V, f[-L] == 0,
) E6 o2 K8 A: ~& |5 E$ y3 c [ f'[-L] == 0}, {f[x]}, x];% J8 x7 b- B, U
M = K /. {V -> 1, L -> 100};) i. s8 m1 E% _ n
Manipulate[) a# [$ D: L6 b: J: E) D0 z" |
Plot[M[[2, 1, 2]], {x, -100, 0},
?; d7 M2 ? `3 n Epilog -> {PointSize[0.01], Black,
9 Z" H% v: e4 u Point[{{a, M[[2, 1, 2]] /. x -> a}, {0,
- O4 _. j/ j n( V/ r' c M[[2, 1, 2]] - x*D[M[[2, 1, 2]], x] /. x -> a}}], Red, Dashed,
" L2 {& w1 u1 K1 F$ I Line[{{a, M[[2, 1, 2]] /. x -> a}, {0,
* m) W5 J) Y0 l7 R9 q8 }) T x @ M[[2, 1, 2]] - x*D[M[[2, 1, 2]], x] /. x -> a}}]}], {a, -100,
) D* C5 k3 F/ {. G( p9 y, a 0}]
- a4 j+ B' e7 G; l9 \Export["1.gif",
# Y+ u3 a) k) K, W/ T5 k Table[Plot[M[[2, 1, 2]], {x, -100, 0}, ) J% V4 \. g/ r% e! e7 r
Epilog -> {PointSize[0.01], Black, " O2 |5 ^5 D8 l x9 I N
Point[{{a, M[[2, 1, 2]] /. x -> a}, {0,
/ v+ S- x$ i% e, q M[[2, 1, 2]] - x*D[M[[2, 1, 2]], x] /. x -> a}}], Red, Dashed,1 x* I4 P1 i; _9 B: B- c; G6 r* H: j
Line[{{a, M[[2, 1, 2]] /. x -> a}, {0, 9 Z$ n$ `4 u) A% y' Z
M[[2, 1, 2]] - x*D[M[[2, 1, 2]], x] /. x -> a}}]}], {a, ! l- \& y& b0 h2 k
Join[Range[-100, -1], {-0.0001}]}]]
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