定积分定义动画演示

402

Clear[f, x, a, b];
. T: q% P6 d$ y$ kf[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 = {};
" m" M5 j3 j9 D! d4 q4 @% W For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
; |, X" L5 q& F3 |  tt1 = Append[tt1,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
) d8 t, O- J5 W, z# y9 x4 N8 I  tt2 = Append[tt2,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
Show[tt1, tt2, g1, DisplayFunction -> $DisplayFunction,
  PlotLabel -> m'' intervals'']]
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定积分的动画演示，运行没有结果，请各位大虾看看错在哪里？
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8 F$ r0 T! |1 g' V! D% k& l2 F3 xf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
* u3 z; v1 L' d- `: _g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
' z0 ^8 a# ~* M. [- x: e: E* k5 Q: L 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]}]}]];
1 i$ K1 A* f/ X* i  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
3 A. V0 K3 Y9 K 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。
! c8 ~7 |0 T$ {+ b* [3 d+ [f[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red];
Animate[t1 = {}; t2 = {};
2 S% P8 I; H8 o  P% G; {3 j% M 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]}]}]];
' B8 l" x2 S) m! e, S& m3 X) ?  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
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

z43742516

收藏起来慢慢看
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meiya

好牛，厉害
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