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;
- @8 d/ J! Y2 S) g$ Z' Z/ zg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
9 d6 B9 w% v; ^9 u+ k; G+ UFor[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,
' z( ^8 W  b4 O  J% }    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
1 b  G7 U* N0 b$ a  tt2 = Append[tt2,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
' t- p$ s7 I2 D) ^( B% m# @ Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
! ]6 J" |) s( b& o9 z  PlotLabel -> m'' intervals'']]
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( `% `* x; h1 |! C$ R* C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？

f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
7 I1 Y: M; q- f3 B 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]}]}]];
7 K  E- n8 F# d5 D9 ~4 }4 x  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

402

已经解决。谢谢小木虫的大虾。
f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
5 w& _3 r5 _9 U  ~3 zg = Plot[f[x], {x, a, b}, PlotStyle -> Red];
7 Q7 g6 i% v: @/ A* qAnimate[t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
2 ?8 N4 m  T" d# ?3 f7 Q  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
7 Y3 @3 `; n( v7 @, p  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
: P2 {# o  i' y: a Show[t1, t2, g, PlotLabel -> n "intervals"], {n, 4, 100, 4},
AnimationRunning -> False]

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
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