定积分定义动画演示

402

Clear[f, x, a, b];
f[x_]： = x^2; a = 0; b = 1.5; m = 0;
, K1 A& |6 d7 a1 i" Fg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
) C! J% K( I  Y8 h9 W  L8 TFor[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
% _4 {) l3 y' X# ]4 c For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
  tt1 = Append[tt1,
: t9 z4 @2 E0 @. g! ~& C    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
; O# B/ Z% M& a/ `1 H$ }( J  tt2 = Append[tt2,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]
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定积分的动画演示，运行没有结果，请各位大虾看看错在哪里？
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1 d/ [( I) Y# M( U) F/ I1 H; s( lf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  DisplayFunction -> Identity]
# Z. Q9 P/ a/ J# E; N7 iFor[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
8 H4 \, m* D' ~9 }) r- O For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
4 l) {1 F) K2 d4 _( O% v7 J5 S$ n  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
/ l5 b1 ^& \# L Show[t1, t2, g, DisplayFunction -> $DisplayFunction,
  PlotLabel -> n "intervals"]]



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变动的永恒

太高端，不懂，帮顶
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402

已经解决。谢谢小木虫的大虾。
4 q  b% ^! r8 Of[x_] := x^2 + 1; a = 0; b = 2; m = 0;
0 u" R: k. S1 Z: |" jg = Plot[f[x], {x, a, b}, PlotStyle -> Red];
Animate[t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
! k) R. y4 q% S" }  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
. a, O" y' r9 t2 M8 z Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
+ U; \8 t' _6 ~6 {8 {& e- c- b* u: S$ J AnimationRunning -> False]
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宏心

牛。牛牛。
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z43742516

收藏起来慢慢看
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z43742516

收藏起来慢慢看

meiya

好牛，厉害