定积分定义动画演示

402

Clear[f, x, a, b];
3 x  ?; s4 G% Q# P" Uf[x_]： = x^2; a = 0; b = 1.5; m = 0;
g1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
For[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,
, D8 v/ a' p+ O2 _    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
% n1 q/ d: F; T* \4 u7 p, X  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？

% ?/ o$ a; E6 G. Cf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  DisplayFunction -> Identity]
1 l8 Q, v7 t3 S* H) o  W+ uFor[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
! ?  c+ K4 G9 V6 k  z For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
, N- N: H+ l1 `3 f$ F  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
8 K/ N' v1 V: u/ a1 V, O4 H) ` 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

402

已经解决。谢谢小木虫的大虾。
f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
% d/ {! a% U5 mg = Plot[f[x], {x, a, b}, PlotStyle -> Red];
) e8 y# b* l- R1 ~Animate[t1 = {}; t2 = {};
( d$ R; |2 }; d4 a 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]}]}]];
" x2 X6 b' n$ w! N  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
) z9 f, d6 R" Q* I8 v4 d  \ Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
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
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meiya

好牛，厉害