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;
' d; C  m' v3 o" H+ Mg1 = Plot[f[x], {x, a, b}, PlotStyle -> {RGBColor[1, 0, 0]},
   DisplayFunction -> Identity];
For[j = 3, j <= 50, j += 2, m = j; tt1 = {}; tt2 = {};
: W" @* V4 S- H7 S For[i = 0, i < m, i++, x1 = a + i*(b - a)/m; x2 = x1 + (b - a)/m;
- c) o! {- z& J) X9 ^# F  tt1 = Append[tt1,
    Graphics[{RGBColor[0, 0, 1], Rectangle[{x1, 0}, {x2, f[x2]}]}]];
  tt2 = Append[tt2,
9 Y9 A: z0 X# G/ u! C    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？

3 c9 |; ]. E+ T: n, \* e9 Z' Sf[x_] := x^2 + 1; a = 0; b = 2; m = 0;
g = Plot[f[x], {x, a, b}, PlotStyle -> Red,
7 Z/ h! L' a9 Q; p  DisplayFunction -> Identity]
For[n = 0, n < 100, n = n + 4; t1 = {}; t2 = {};
: _8 H, w5 R, _" F# q/ _ For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
# B# L$ W5 Y3 r% k5 c* ~  t1 = Append[t1,
    Graphics[{Blue, Rectangle[{x1, f[x1]}, {x2, f[x2]}]}]];
  t2 = Append[t2, Graphics[{Green, Rectangle[{x1, f[x1]}, {x2, 0}]}]]];
3 T5 x: a" u5 H9 p4 ?8 j% k! W Show[t1, t2, g, DisplayFunction -> $DisplayFunction,
# l( n1 M" L0 a0 ~) v7 y, K# |/ S0 ?/ R  PlotLabel -> n "intervals"]]
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+ i% E) M- Y! ?1 D2 h0 h) J
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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;
4 O% K( u5 m' Q4 T9 x$ Sg = Plot[f[x], {x, a, b}, PlotStyle -> Red];
Animate[t1 = {}; t2 = {};
For[i = 0, i < n, i++, x1 = a + (b - a) i/n; x2 = x1 + (b - a)/n;
  t1 = Append[t1,
) l9 c5 \) M$ {: r' }    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。

z43742516

收藏起来慢慢看

z43742516

收藏起来慢慢看

meiya

好牛，厉害