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;
% ?2 x0 l; c& ~6 a. Hg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
/ s5 G* q* C, ?" H/ t5 Z, L. g   DisplayFunction -> Identity];
" z* x. I% ^$ J' f/ cFor[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
  tt1 = Append[tt1,
5 N& D' L0 }4 D    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
  tt2 = Append[tt2,
1 J! U) e( g9 C. |9 C" _3 T    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
; [3 \, _- @5 w, B  d Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]

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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f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
9 K& O& P' n1 }  _6 k- Cg = Plot[f[x], {x, a, b}, PlotStyle -> Red,
' f; P. @. r$ W4 O( i7 P  DisplayFunction -> Identity]
( g0 r5 T- |+ ]* X7 b0 zFor[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
! h/ A& f* }0 {9 n. F6 O For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
& ~. I0 Y( d/ X1 ?$ K$ k6 L7 M  t1 = Append[t1,
, n  Y/ _0 M& L4 _2 b+ ]3 k, l    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[t1, t2, g, DisplayFunction -> $DisplayFunction,
- l. @- h, E: Y) p5 D  PlotLabel -> n "intervals"]]
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! y! W$ l" b7 g' s, ]( F& j# j, ^

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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。
/ B% z" C* V# }: }* J* o6 \f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
( \0 x5 U0 @2 K" d$ a6 T4 Ng = Plot[f[x], {x, a, b}, PlotStyle -> Red];
8 k  @+ L8 S1 b" eAnimate[t1 = {}; t2 = {};
3 y9 K  W7 g/ x4 Q5 }* B) ~9 Q 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]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
AnimationRunning -> False]

宏心

牛。牛牛。
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z43742516

收藏起来慢慢看

z43742516

收藏起来慢慢看

meiya

好牛，厉害