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;
g1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
4 `  W0 [" T4 U! _% Y# d7 v7 fFor[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,
' R7 k7 U: D5 J) G. P" S    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
  tt2 = Append[tt2,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]

% T0 o# i: f' g5 ^2 d7 m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;
4 M# w& j+ `7 M6 P! ^; Hg = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  DisplayFunction -> Identity]
1 S* @: F2 r% J2 w9 k1 s& }; i$ a$ S- bFor[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
9 p" z% r- c: Y& {. N    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,
  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。
% z4 V3 D7 K: \3 x- F4 [f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
Animate[t1 = {}; t2 = {};
9 [$ t4 @2 b  I- Y For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
+ i8 m7 L+ _- M, J  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
. j" x# f/ `0 n5 G. m Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
AnimationRunning -> False]
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宏心

牛。牛牛。

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